Rotary dobby and weaving loom comprising such a dobby

Abstract

The present invention relates to a rotary dobby for a loom comprising a frame, a main shaft, an output lever shaft, a subassembly (200') formed of a first blade (202) and at least one second blade (204), mounted adjacently. The subassembly includes a first output lever (42) and a first actuating rod (52) belonging to the first blade (202), a second output lever (44) and a second actuating rod (54) belonging to the second blade (204), an eccentric (56), mounted around the main shaft, comprising a first zone (56A) configured to cooperate with the first rod (52), a second zone (56B) configured to cooperate with a guide ring (59) and a third zone (56C) configured to cooperate with the second rod (54), and a coupling device (210).

Description

[0001] The present invention relates to a rotating dobby for a loom, as well as a loom comprising such a dobby.

[0002] The invention relates to the field of looms and their sheaf-forming machines, in particular to the field of rotary darters for controlling heddle frames.

[0003] In the weaving industry, it is common practice to use dobby-type heddle-forming machines to control heddle frames. In rotary dobby machines, the reciprocating vertical movement of the heddle frames is achieved by drawing mechanisms driven by actuating elements attached to blades. These actuating elements are mounted on a main shaft of the dobby machine, which rotates intermittently. Each time this shaft stops, a heddle mechanism engages the actuating element with the shaft to control an oscillating part, according to the desired weave pattern of the fabric being woven.

[0004] During weaving, when a frame does not need to be moved up or down, the associated eccentric is held in its angular position by restraint and immobilization means such as assemblies of beaks and return springs.

[0005] Certain textile applications, particularly carpet weaving, involve swarm formation with significant dynamic frame forces. These dynamic forces increase when the frame is in a high or low position.

[0006] EP 1 845 181 A1 describes a rotary dobby for a loom comprising, for each oscillating connecting rod-lever assembly, an eccentric-type actuation element for driving a connecting rod, thereby inducing the oscillating reciprocating motion of a heddle frame. When the eccentric needs to be held in an angular position, tabs on the eccentric cooperate with a retaining arm.

[0007] EP 1 382 725 A1 and EP 3 556 920 A1 describe other rotary ratchets in which each frame is driven by an oscillating connecting rod and lever assembly controlled by an eccentric. The angular position of the eccentric is maintained by the interaction of elements of the smoothing device with spurs formed on the eccentric.

[0008] However, these different dobby designs are not suitable for weaving applications where the dynamic forces of the frame transmitted to a heddle, particularly to the eccentric driving the heddle, are significant, and also where the tension forces on the warp threads are substantial. In particular, the forces exerted when the eccentric must be held in an angular position are such that the restraint and immobilization means described in the prior art do not adequately hold the eccentric, to the point that the heddle frames may shift unexpectedly.

[0009] The invention therefore aims to remedy this drawback by providing a new rotating darter capable of withstanding significant stresses, particularly due to the tension of the warp threads, including when the heddle frames are in the high or low position of their vertical oscillating stroke.

[0010] The invention relates to a rotary dobby for a loom comprising a frame, a main shaft supported by the frame and extending along a main axis, an outfeed lever shaft supported by the frame and extending along a common axis parallel to the main axis, and at least one sub-assembly consisting of a first blade and at least one second blade, mounted adjacently and defining respectively a first plane perpendicular to the main axis and a second plane perpendicular to the main axis. The sub-assembly comprises a first outfeed lever belonging to the first blade and a second outfeed lever belonging to the second blade, the first and second outfeed levers being adjacent along the common axis, mounted to rotate freely around the outfeed lever shaft and driven by an alternating oscillating motion during weaving, and a first connecting rod belonging to the first blade.attached to the first output lever and mounted for rotational movement around the main shaft, a second actuating rod belonging to the second blade, attached to the second output lever and mounted for rotational movement around the main shaft, an eccentric mounted around the main shaft and comprising a first zone configured to cooperate with a first zone of the first connecting rod by constituting a first articulation, through which the eccentric and the first actuating rod pivot relative to each other about a first axis parallel to the main axis, a second zone configured to cooperate with a guide ring carried by the main shaft by constituting a second articulation, through which the eccentric and the main shaft pivot relative to each other about the main axis, and a coupling device,capable of selectively locking the main shaft and the eccentric in rotation in a coupled configuration of the coupling device, and of allowing the eccentric to rotate freely relative to the main shaft in a decoupled configuration of the coupling device. According to the invention, the eccentric comprises a third zone configured to cooperate with a first zone of the second connecting rod by constituting a third joint, through which the eccentric and the second connecting rod pivot relative to each other about the first axis.

[0011] Thanks to the invention, the forces exerted by a frame of rails are distributed over two blades whose movement is synchronized by means of a common eccentric, this synchronization allowing an optimized vertical alternating movement of the frame of rails.

[0012] According to other advantageous aspects of the invention, the rotary dobby for a loom comprises one or more of the following features, taken individually or in any technically possible combination: The coupling device comprises a drive unit fixed to the main shaft, and two locking mechanisms, hinged to the eccentric and adapted to cooperate with the drive unit in the coupled configuration of the coupling device to lock the eccentric and the main shaft in rotation about the main axis. The first hinge includes a first bearing interposed radially to the first axis, between the eccentric and the first connecting rod; the second hinge includes a second bearing interposed radially to the main axis, between the eccentric and the main shaft; and the third hinge includes a third bearing interposed radially to the first axis, between the eccentric and the second connecting rod. The second bearing includes rollers that extend parallel to the main shaft, overlapping the first and second planes.The eccentric comprises a cylindrical element having two flanks separated by an axial distance greater than an axial distance between the first and second planes, an external peripheral surface defining the first zone as a first raceway for the first bearing and the third zone as a third raceway for the third bearing, and a bore whose inner surface defines the second zone as a second raceway for the second bearing. The eccentric includes retaining means, and the ratchet mechanism includes means for securing the eccentric, the securing means being configured to engage with the retaining means when the coupling device is in the uncoupled configuration or when the eccentric is in a resting position around the main shaft.First immobilizing means are mounted on a front surface of the first actuating rod or on a front surface of the second actuating rod and include elastic return means configured to return the immobilizing means to the engagement position with the retaining means. The ratchet mechanism includes second immobilizing means adapted to selectively actuate the coupling device between the decoupled and coupled configurations in the eccentric's rest position. A first retaining means and a first immobilizing means are centered on a third plane perpendicular to the principal axis and located between the first and second planes. The coupling device is centered on a fourth plane perpendicular to the principal axis, and a second retaining means and a second immobilizing means are centered on this fourth plane.The first and / or second retaining means comprises a plate centered on the third or fourth plane perpendicular to the main shaft and riveted to one side of the cylindrical element of the eccentric. The cylindrical element of the eccentric comprises a chamber disposed between the two sides of the cylindrical element, having an opening on the external peripheral surface of the cylindrical element and configured to receive at least partially a plate belonging to the first retaining means. The ratchet mechanism includes a modulator configured to mechanically modulate the rotation of the main shaft based on the rotation of a ratchet control shaft, and, during the continuous rotation of the control shaft, the main shaft undergoes a rotary motion characterized by an alternating movement of amplitude at the eccentric's stopping position.

[0013] The invention also relates to a loom comprising a rotating dobby as mentioned above and a draw mechanism for controlling a heddle frame, this draw mechanism comprising at least one set of connecting rods and return levers coupling the heddle frame to the first and second heddles and configured to return an alternating oscillating motion from the first output lever and the second output lever to the heddle frame, the heddle frame having an alternating motion between a high position and a low position.

[0014] According to other advantageous aspects of the invention, the loom comprises one or more of the following features, taken individually or in any technically possible combination: The draw mechanism comprises a first drawbar, coupled to the first release lever of the first slat, which drives at least one return lever to which a first frame link is attached, and a second drawbar, coupled to the second release lever of the second slat, which drives at least one return lever to which a second frame link is attached. The first and second frame links are attached to the same frame of rails. The draw mechanism includes a first and a second adjustable clip, mounted respectively on the first and second release levers of the dribble and configured to ensure the pivoting assembly and adjustment of the first and second release levers with the draw mechanism. The clips are secured to each other.

[0015] The invention will become clearer upon reading the following description of two embodiments of a rat trap and a loom conforming to its principle, given solely by way of non-limiting example, and made with reference to the drawings in which: [ Fig. 1 ] there figure 1 is a partial view of a loom conforming to a first embodiment of the invention, incorporating a dobby according to the invention; [ Fig. 2 ] there figure 2 is an exploded perspective view of the twin blades of the loom figure 1 ; Fig. 3 ] there figure 3 is a perspective view, hood open, of the rat trap of the figure 1 , [ Fig. 4 ] there figure 4 is a perspective view of a mechanism for actuation of the twin blades of the figure 2 , insert A highlighting the leading blade and insert B highlighting the driven blade, [ Fig. 5 ] there figure 5 is a partial exploded view of the actuation mechanism of the figure 4 , [ Fig. 6 ] there figure 6 is a partial front view of the actuation device of the figure 4 , [ Fig. 7 ] there figure 7 is a perspective view analogous to insert A) of the figure 4 , of a twin-blade actuation mechanism of the type of those of the figure 2 , this actuation mechanism belonging to a rat trap according to a second embodiment, and [ Fig. 8 ] there figure 8 is a graphical representation of the motion law of the ratier modulator of the figure 3 , [ Fig. 9 ] there figure 9 is a perspective view of a device for adjusting the length of the connecting rods of the loom figure 1 .

[0016] There figure 1 shows a partial view of a loom M according to the invention. The loom M comprises heddle frames 2, of which only two are shown in the figure 1 for the sake of simplification and which are each operated by a pulling mechanism 4 connected to a rotating ratchet R.

[0017] The rotary darter R is a loom-forming machine for the loom M whose function is to actuate the 4 draw mechanisms of the heddle frames 2, to determine the weave of the fabric produced by the loom M.

[0018] The loom includes a warp beam E, on which warp yarns 6 are wound before passing through eyelets 8a belonging to heddles 8 carried by heddle frames 2. Insertion means, not shown, allow one or more weft yarns to be inserted into the sheaf formed by the warp yarns moved vertically by the heddle frames 2, so as to form at least one fabric T which is wound onto a bobbin B, at the exit of the loom M.

[0019] To the figure 1 , only a few warp threads 6 and a few heddles 8 are shown, for clarity of drawing.

[0020] A draw mechanism 4 comprises, for each frame of rails 2, an assembly consisting of connecting rods to the frame, return levers, at least one horizontal connecting rod and at least one attack connecting rod connected, by means of a clip, to a blade of the rotating dribble R.

[0021] The rotary dobby R and consequently the loom M according to the invention comprise two types of blades: single blades 200 and subsets 200' of twin blades.

[0022] For a first type of draw mechanism 4, the connecting rods to the frame 10 are attached to the frame of rails 2 and mounted by means of the return levers 12 on a horizontal connecting rod 14. The horizontal connecting rod 14 is connected to an attack connecting rod 16. The attack connecting rod 16 is connected by means of a clip 18 to a single blade 200 of the rotating draught R.

[0023] Each single blade 200 actuates, via a pulling mechanism 4, a frame of rails 2. Only one single blade 200 is shown in the figures and actuates, via the associated pulling mechanism 4, the frame of rails 2 shown furthest back and to the right. figure 1 The 4-drawing mechanism associated with a single 200 blade includes, for example, four connecting rods to the frame 10. The single 200 blades are of the type of those of the rat nets described in EP 1 845 181 A1, EP 1 382 725 A1 and EP 3 556 920 A1.

[0024] Only one sub-assembly 200' is shown in the figures and actuates, via the associated pulling mechanism 4, the frame of rails 2 shown furthest forward and to the left at the figure 1 .

[0025] Each subset 200' comprises two paired blades 202 and 204, namely a first single blade 202 and an adjacent second single blade 204. The first blade 202 can be referred to as the "leading" blade and the second blade 204 as the "led" blade. A subset 200' of paired blades 202 and 204 can also be called a double blade.

[0026] A pull mechanism 4 associated with a subassembly 200' is of a second type and allows a single rail frame 2 to be operated from the first and second twin blades 202 and 204 of this subassembly 200'. Such a pull mechanism 4 is shown in the figure 2 .

[0027] The first blade 202 is connected to a first connecting rod 162 by a clip 182. The first connecting rod 162 is connected to a first horizontal connecting rod 142. The first horizontal connecting rod 142 drives a plurality of first return levers 122. On at least one return lever 122, a first connecting rod to the frame 102 is attached. The first connecting rods to the frame 102 are attached to the rail frame 2, more particularly to its lower cross member 2a.

[0028] The second blade 204 is connected to a second connecting rod 164 by a clip 184. The second connecting rod 164 is connected to a second horizontal connecting rod 144. The second horizontal connecting rod 144 drives a plurality of second return levers 124. A second connecting rod to the frame 104 is attached to at least one return lever 124. The second connecting rods to the frame 104 are attached to the rail frame 2, more particularly to its lower cross member 2a.

[0029] The first connecting rods to the frame 102 and the second connecting rods to the frame 104 are attached to the same frame of rails 2, preferably to the same lower cross member 2a. The first and second blades 202 and 204 of the double blade 200' therefore actuate the same frame of rails 2. The simultaneous actuation of the same frame of rails 2 by the two twin blades 202, 204 of a sub-assembly 200' makes it possible to distribute the forces exerted by the frame of rails 2 onto the two blades 202, 204.

[0030] In the example of the figure 2 The frame of runners 2 is driven by a pair of connecting rods to the frame 102 and by a pair of connecting rods to the frame 104. The pairs of connecting rods to the frame 102 and 104 are adjacent.

[0031] The connecting rods to the frame 104 actuated by the second blade 204 are positioned closest to the ratchet R, on the frame of rails 2, relative to the connecting rods to the frame 102 actuated by the first blade 202.

[0032] Alternatively, other distributions of the connecting rods to the frame 102 and 104 are conceivable.

[0033] Clips 18, 182, and 184 secure the connecting rods 16, 162, and 164 to the blades 200, 202, and 204, respectively. The positioning of clips 18, 182, and 184 is adjustable vertically along the length of the blades 200, 202, and 204. This vertical positioning determines the size of the crowd formed downstream of the rail frame 2. On the figures 2 à 5 The clips 182 and 184 of the blades 202 and 204 are positioned at their maximum height. This maximum height allows for the largest possible crowd amplitude.

[0034] Advantageously, the clip 182 of the first blade 202 and the clip 184 of the second blade 204 are joined together. This joining allows for a common adjustment of the crowd amplitude for blades 202 and 204 and ensures optimal vertical movement of the rail frame 2.

[0035] Advantageously, the joining of the first and second clips 182 and 184 is achieved by means of a key 186 which passes through two holes 188 respectively formed in the first and second clips. On the figures 3 And 4 , the key 186 is represented by its longitudinal axis and only the orifice 188 of the first clip 182 is visible.

[0036] In practice, the loom M comprises several single blades 200 and several twin blades 202, 204 forming subsets 200'. For example, eight single blades 200 driving eight heddle frames 2 and eight twin blades 202, 204 forming four subsets 200' driving four heddle frames 2. Other numbers of single and twin blades are conceivable as alternatives.

[0037] According to another embodiment not shown, the loom M comprises only twin blades 202, 204.

[0038] The proper execution of the vertical movement of the frame of rails 2 actuated by the sub-assembly 200' is ensured by the synchronized movement of the twin blades 202, 204.

[0039] The rotary rat net R includes, for each pair of twin blades 202, 204, a twin blade drive device 206 which is described in detail later in the description.

[0040] As seen on the figure 3 The rotary rat trap R comprises a frame 22, which forms a fixed part of the trap R. The frame 22 is a rigid structural component of the trap R. The frame 22 is advantageously a cast part, or possibly an assembly of welded parts. A cover, not shown, is attached to the frame 22. The frame 22 and the cover define an internal volume of the rotary rat trap R, enclosing the various internal parts of the trap R described below.

[0041] The frame 22 includes a base 22A. The frame 22 includes two support plates 23 and 24, located in the internal volume of the frame 22. The plates 23 and 24 project upwards from the base 22A of the frame 22.

[0042] The rat net R comprises a main shaft 32 supported by the frame 22, within its internal volume. The main shaft 32 is supported at one end by the plate 23, via a pivot joint of the plate 23, and at an intermediate part of the main shaft 32 by the plate 24, via a pivot joint of the plate 24. The main shaft 32 extends along a main axis X32 which is an axis of rotation of the main shaft.

[0043] The rat trap R includes an exit lever shaft 34 supported by the frame 22 within its internal volume. The exit lever shaft 34 is supported at its ends by the plates 23 and 24. The exit lever shaft 34 extends along a common axis X34. The common axis X34 is parallel to the main axis X32. The lever shaft 34 is preferably fixed in rotation about its axis X34 relative to the frame 22.

[0044] The main shaft 32 is driven by an intermittent rotational movement with a stop every half-turn.

[0045] The rotation of the main shaft 32 is achieved by a modulator 36 and a bevel gear 38 comprising a ring gear 38a and a pinion 38b. The modulator 36, adjacent to the plate 24, is mechanically connected to the main shaft 32. The bevel gear 38 is mechanically connected to a drive shaft 40 of the ratchet mechanism R. The drive shaft 40 is partially located outside the frame 22 and extends along an axis X40 perpendicular to the axis X32. The modulator 36 and the bevel gear 38 transform the continuous rotational motion of the drive shaft 40 into the intermittent rotational motion of the main shaft 32.

[0046] The main shaft 32 has a drive function for driving the blades 20. To do this, the main shaft 32 receives a series of drive devices enabling the movement of each blade 20.

[0047] A single blade 200 and a double blade 200' with a pair of twin blades 202, 204 are shown on the figure 3 .

[0048] Each single blade 200 is associated with a drive device of the type of drive device described in detail in EP 1 845 181 A1.

[0049] Each pair of twin blades 202, 204 is associated with a drive device 206 shown on the figures 4 à 6 Advantageously, the R-shaped rat net includes as many twin-blade drive devices as there are pairs of twin blades 202, 204, i.e., double blades 200'. In practice, in a standard-sized rotary rat net, one can provide, for example, between two and eight pairs of twin blades 202, 204 and thus between two and eight drive devices 206 for twin blades 202, 204.

[0050] The drive device 206 includes a kinematic chain 208 coupled to a coupling device 210. These two elements 208 and 210 allow the rotation of the main shaft 32 to be selectively bound, that is to say, linked, to the movement of the blades 202, 204.

[0051] The first blade 202 includes a first output lever 42 and a first actuating rod 52. The first blade 202 defines a first plane P2 perpendicular to the main axis X32.

[0052] The second blade 204 includes a second output lever 44 and a second actuating rod 54. The second blade 204 defines a second plane P4 perpendicular to the main axis X32.

[0053] The first exit lever 42 is preferably flat and thin, like a plate. The first exit lever 42 is partially contained within the frame 22, with a first portion supported by the shaft of the exit levers 34 and a second portion in the form of an arm extending out of the ratchet R through the cover. For this purpose, the cover of the ratchet R has one or more openings. The first exit lever 42 is mounted to rotate freely around the shaft of the exit levers 34.

[0054] A plain bearing 43, including for example a bronze bushing, provides the interface between the first output lever 42 and the output lever shaft 34.

[0055] As an alternative not shown, the plain bearing 43 can be replaced by a ball or roller bearing.

[0056] During weaving, the first output lever 42 is animated by an alternating oscillating movement around the common axis X34.

[0057] As is known, the first actuating rod 52 is coupled to the first output lever 42.

[0058] The first connecting rod 52 is mounted to rotate freely around the main shaft 32.

[0059] The first actuating rod 52 is articulated on an eccentric 56.

[0060] The eccentric 56 comprises a cylindrical element 57. The cylindrical element 57 is defined by two flat flanks 571 and 572, an external peripheral surface 573 and a central bore 574.

[0061] Preferably, the cylindrical element 57 is a single piece. In an alternative not shown, the cylindrical element 57 is made of two parts which are screwed or welded together.

[0062] The two flat sides 571 and 572 of the cylindrical element 57 are spaced apart by an axial gap, measured along the main axis X32, greater than the axial distance, measured along the main axis X32, between the first plane P2 defined by the first blade 202 and the second plane P4 defined by the second blade 204.

[0063] A first zone 52A of the first actuating rod 52 cooperates with a first zone 56A of the eccentric 56 to form a first articulation. Through this first articulation, the first actuating rod 52 and the eccentric 56 are pivotable relative to each other about a first axis X1 parallel to the main axis X32, but radially offset from it by a non-zero distance.

[0064] The first zone 52A of the first connecting rod 52 corresponds to the inner surface of a central bore of the connecting rod 52. Preferably, as shown on the figure 5 , the first zone 52A accommodates a cage 521 and balls 522 defining a first bearing.

[0065] The first zone 56A of the eccentric 56 belongs to the external peripheral surface 573 of the cylindrical element 57 of the eccentric 56. The first bearing is interposed, radially to the axis X1, between the first actuating rod 52 and the eccentric 56. The first zone 56A of the eccentric constitutes a first bearing raceway for the first bearing.

[0066] The second output lever 44 is preferably of the same shape as the first output lever 42. Similar to the first output lever 42, the second output lever 44 is partially contained within the internal volume of the frame 22. The second output lever 44 is mounted to rotate freely around the output lever shaft 34, which is thus a common shaft for the various levers. The second output lever 44 is adjacent to the first output lever 42 along the common axis X34. The first output lever 44 undergoes the same reciprocating oscillating motion during weaving as the first output lever 42.

[0067] A plain bearing 43, or alternatively a ball or roller bearing, provides the interface between the second output lever 44 and the output lever shaft 34. As with the first lever, the plain bearing may include a bronze bushing.

[0068] The second actuating rod 54 is coupled to the second output lever 44. The second actuating rod 54 is mounted to rotate freely around the main shaft 32.

[0069] The second actuating rod 54 is also articulated on the eccentric 56.

[0070] A first zone 54A of the second actuating rod 54 cooperates with a third zone 56C of the eccentric 56 to form a third joint. Through this third joint, the second actuating rod 54 and the eccentric 56 are pivotable relative to each other about the first axis X1.

[0071] The first zone 54A of the second connecting rod 54 corresponds to the inner surface of a central bore of the connecting rod 54. Preferably, the first zone 54A accommodates a cage 541 and balls 542 defining a third bearing.

[0072] The third zone 56C of the eccentric 56 belongs to the external peripheral surface 573 of the cylindrical element 57 of the eccentric 56. The third bearing is radially interposed between the second actuating rod 54 and the eccentric 56. The third zone 56C constitutes a third bearing raceway for the third bearing.

[0073] Advantageously, the first zone 56A, constituting the first raceway for the first bearing articulating the first connecting rod 52 to the eccentric 56, and the third zone 56C, constituting the third raceway for the third bearing articulating the second connecting rod 54 to the eccentric 56, belong to the same surface 573, ensuring perfect parallelism of the articulations linking the connecting rods 52, 54 to the eccentric 56.

[0074] As an alternative not shown, balls 522 and / or 542 can be replaced by rollers.

[0075] According to another variant, also not shown, the inner surface of the central bore of the first actuating rod 52 and / or the second actuating rod 54 includes a groove configured to receive as support balls or rollers carried by the first zone 56A and / or the third zone 56C of the eccentric 56 and define a first bearing and / or a third bearing.

[0076] In another variant not shown, the central bore of the first connecting rod 52 corresponding to the first zone 52A and / or the central bore of the second connecting rod 54 corresponding to the first zone 54A receives a plain bearing or a bushing. The plain bearing or bushing is interposed radially to the axis X1, between the first actuating rod 52 and the eccentric 56 and / or between the second actuating rod 54 and the eccentric 56, so as to form the first articulation which is a pivot joint between the first actuating rod 52 and the eccentric 56 and / or the third articulation which is a pivot joint between the second actuating rod 54 and the eccentric 56. Alternatively, the bearing or bushing can be mounted slidingly, or press-fitted, or even be a single piece of the eccentric 56, the first actuating rod 52 or the second actuating rod 54.

[0077] The eccentric 56 is common to the first actuating rod 52 and the second actuating rod 54. Advantageously, the eccentric 56 is shared by the two twin blades 202 and 204 forming the subassembly 200'. This shared use ensures the synchronized actuation of the blades 202 and 204 by the eccentric 56.

[0078] To enable this synchronized actuation, the eccentric 56 is articulated to a guide ring 59 carried by the main shaft 32. A second zone 56B of the eccentric 56 cooperates with the guide ring 59 to form a second articulation. Through this second articulation, the eccentric 56 and the main shaft 32 are pivoted relative to each other about the main axis X32.

[0079] The guide ring 59 carries on its outer peripheral surface a cage 591 and rollers 592, which together define a pivot zone 59A for the guide ring 59, in the form of a second bearing. The rollers 592 of the second bearing extend parallel to the main shaft 32, overlapping the first plane P2 defined by the first blade 202 and the second plane P4 defined by the second blade 204. The width of the rollers 592, measured parallel to the main axis X32 and greater than in the drive mechanism of a single blade 200, allows them to withstand significant forces transmitted by the rail frames 2 to the draw mechanism 4 and ensures a longer bearing life. This is particularly advantageous for a bearing diameter where the dimensions in plane P2 or plane P4 cannot easily be revised without considerably increasing the overall machine size.

[0080] The second zone 56B of the eccentric 56 belongs to the inner surface of the bore 574. The second bearing is interposed, radially to the main axis X32, between the guide ring 59 and the eccentric 56. The second zone 56B of the eccentric constitutes a second bearing raceway for the second bearing.

[0081] As an alternative not shown, the 592 rollers can be replaced by balls.

[0082] According to another variant, also not shown, the outer surface of the guide ring 59 includes a groove configured to receive as support balls or rollers carried by the second zone 56B of the eccentric 56 and define a second bearing.

[0083] In an alternative version not shown, the bore 574 of the eccentric 56 receives a plain bearing or bushing. The plain bearing or bushing is interposed, radially to the central axis X32, between the eccentric 56 and the guide ring 59 so as to form the second joint which is a pivot joint between the eccentric 56 and the guide ring 59.

[0084] The drive device 206 also includes a coupling device 210. The coupling device 210 is capable of selectively locking, in rotation around the main axis X32, the main shaft 32 and the eccentric 56 in a coupled configuration of the coupling device 210, and of leaving the eccentric 56 free, in rotation around the main axis X32, relative to the main shaft 32 in a decoupled configuration of the coupling device 210.

[0085] In other words, when the coupling device 210 is in a coupled configuration, the rotation of the main shaft 32 sets the first output lever 42 and the second output lever 44 in synchronized motion. In the decoupled configuration of the coupling device 210, the output levers 42 and 44 are not set in motion by the main shaft 32, whether the main shaft 32 is rotating or stationary. Preferably, in the decoupled configuration, the output levers 42 and 44 are held in a fixed position relative to the frame 22, the position in which the levers 42 and 44 were left when the coupling was switched to the decoupled configuration. For example, this position corresponds to a high or low position of the associated rail frame 2.

[0086] Advantageously, the coupling device 210 includes a driver 62, a pair of locks 64 and 65, a slide 68 (visible on the figure 6 ) and a 70 smoothing device.

[0087] Between two contiguous eccentrics 56, the main shaft 32 is rotationally fixed to the driver 62, whose central opening O62 is substantially circular and provided with two teeth 621. The two teeth 621 are engaged in longitudinal grooves of corresponding shapes 32a formed on the periphery of the main shaft 32. The outer peripheral edge 622 of the driver 62 is provided with four notches 63 which define four shoulders 622A, 622B, 622C, 622D formed in the edge of the driver 62.

[0088] Two locks, 64 and 65, visible in detail on the figure 6 , are respectively articulated around two shafts 66A and 66B fixed on the eccentric 56 and each defining an axis of rotation X64 and X65 of the locks 64 and 65. The axes X64 and X65 are parallel to the main axis X32.

[0089] The first lock 64 comprises a first arm 641 extending radially about the axis X64, the end 642 of which can be engaged in two of the notches 63, such that its terminal surface 643 can then bear against one of the shoulders 622A and 622C. The lock 64 also comprises a second radial arm 644, the end 645 of which is engaged in a fork formed at the end 681 of a slide 68. The slide 68 is mounted on the eccentric 56 and is free to move in both directions along a radial direction D68 about the main axis X32. The first lock 64 is also subjected to the action of an elastic return means, for example, a return spring 67.

[0090] The second lock 65 has the same geometry as the lock 64 and comprises two arms 651 and 654 which extend radially with respect to X65 and whose respective ends 652 and 655 are intended to cooperate respectively with the shoulders 622B and 622D and with the slide 68. The terminal surface 653 of the arm 651 is intended to come selectively into contact with the shoulders 622B and 622D.

[0091] When the driver 62 is driven by the main shaft 32 in the direction of arrow F62 of the figure 6 , surfaces 653 and 622B form a first interface for transferring a rotational force from the driver 62 to the eccentric 56. Surfaces 643 and 622A form a second interface for transferring the rotational force from the driver 62 to the eccentric 56.

[0092] In other words, when the coupling device 210 is in the coupled configuration, the locks 64 and 65 are engaged in notches 63 of the driver 62. The rotation of the main shaft 62 is then transmitted to the eccentric 56. The eccentric 56 sets in motion, in a synchronized manner by the actuating rods 52 and 54, respectively the first output lever 42 and the second output lever 44.

[0093] When the coupling device 210 is in the decoupled configuration, the locks 64 and 65 are disengaged from the notches 63 of the driver 62. The rotation of the main shaft 32, therefore the rotation of the driver 62, is not transmitted to the eccentric 56 and the output levers 42 and 44 remain in the fixed position.

[0094] According to an advantageous aspect of the invention, the fork formed at the end 681 of the slide 68 is symmetrical with respect to the plane defined by the axis X32 and by the direction D68. The fork formed at the end 681 of the slide cooperates identically with the end 645 of the first lock 64 and with the end 655 of the second lock 65. In other words, the slide 68 actuates the two locks 64 and 65 in a similar and synchronized manner. Likewise, the slide 68 transmits the movement of one lock 64, 65 to the other lock 64, 65 in a similar and synchronized manner.

[0095] It is possible to implement coupling devices 210 with a different operating mode than that described in this example, without departing from the scope of the invention, provided that these coupling devices 210 have the aforementioned coupled and decoupled configurations.

[0096] The slide 68 is intended to be actuated by the end beak 711 or 721 of an oscillating lever 71 or 72 controlled by the smoothing device 70. The oscillating levers 71, 72 are located on the front surface 52B of the first actuating rod 52. The oscillating levers 71 and 72 are subjected to the action of two return springs 73 which tend to bring the beaks 711 and 721 into engagement with the slide 68 against a force exerted by the smoothing device 70. The smoothing device 70 is analogous to the smoothing device described in detail in EP 1 845 181.

[0097] When the terminal beak 711 or 721 of an oscillating lever 71 or 72 applies a centripetal force on the slide 68, against the return spring 67, the two locks 64 and 65 pivot around their respective axes X64 and X65, in a direction of disengagement of the arms 641 and 651 outwards from the notches 63.

[0098] When the end beak 711 or 721 does not apply force to the slide 68, the action of the return spring 67 returns the latch 64 to an engaged position with the driver 62. In the engaged position, the end surface 643 of the latch 64 bears against one of the shoulders 622A and 622C. As it pivots around the axis X64 to return to the engaged position, the latch 64 exerts a centrifugal force on the end fork 681 of the slide 68 with respect to the central axis X32. The slide 68 moves along the direction D68, away from the main axis X32. This outward translation of the slide causes the latch 65 to rotate around the axis X65. The latch 65 is then returned to an engaged position with its arm 651 in the opposite notch 63. In the engaged position, the terminal surface 653 of the lock 65 comes to rest against one of the shoulders 622B and 622D of the trainer.

[0099] In other words, the switching of the coupling device 210 from a coupled configuration to a decoupled configuration is controlled by the smoothing device 70 which then exerts a centripetal force by means of one of its oscillating levers 71 and 72 on the slide 68.

[0100] It is possible to implement other forms of slide 68 than the one described in this example. Another operating mode of the slide 68 that can be implemented, without departing from the scope of the invention, is described in EP 1 845 181 A1.

[0101] Advantageously, the activation of the two twin blades 202 and 204 requires only a coupling device 210 and a smoothing device 70. The sharing of the coupling device 210 and the smoothing device 70 ensures the synchronization of the actuation of the twin blades 202 and 204 and a saving of space in particular along the main shaft 32.

[0102] Advantageously, the identical and synchronized actuation of the two latches 64 and 65 by the slide 68 allows both latches 64 and 65 to be disengaged from the notches 63 of the drive 62 without any time lag. This is important in the application of this dobby, where the tension forces on the warp threads during the opening of the sheaf can be very high. These significant tension forces are directly transmitted to the latches 64 and 65 engaged in the drive 62.

[0103] These significant efforts also require a modification of the dynamics of the main tree 32.

[0104] The switching of the coupling device 210 between the coupled configuration and the decoupled configuration is done under the control of the smoothing device 70 at each stopping time of the main shaft 32, i.e. at each rotation of half a turn of the main shaft 32.

[0105] In this ratchet R, where the locks 64 and 65 are subjected to significant stress, the stopping time of the main shaft 32 does not allow for easy release of the locks 64 and 65. This is particularly true when the driver 62 is driven by the main shaft 32 in the direction of arrow F62 of the figure 6 , the lock 65 is heavily loaded so that it presses on the shoulder 622B, because of the tension of the chain wires which transmits forces to the frame 2 and to the eccentric 56, and does not easily disengage from the notch 63.

[0106] To overcome this difficulty, the modulator 36, and in particular its cam tracks, are modified. As illustrated in the figure 8 The modulator 36 transforms the continuous rotation θ of the control shaft 40 from 0° to 360° into an intermittent rotational movement θ' of the main shaft 32. The main shaft 32 first rotates from 0° to 180°, i.e., a half-turn, for example, clockwise. Then, instead of stopping at the end of this half-turn, i.e., instead of maintaining a fixed angular position θ' at θ'=180°, the movement is alternating. The angle of rotation θ' decreases by an amplitude Δθ', and the main shaft 32 rotates by an amplitude Δθ' counterclockwise. The amplitude Δθ' of the alternating movement is advantageously between 0.5° and 5°, preferably equal to 1°.

[0107] During this alternating movement of the main shaft 32, the smoothing device 70 can control the release of the locks 64 and 65 from the notches 63 of the driver 62.

[0108] The main shaft 32 then makes a new rotation in the clockwise direction from 180° to 360°, that is to say a new rotation of half a turn, so as to travel in total a complete rotation, i.e. 360°, when the control shaft makes a complete rotation.

[0109] The alternating movement produced makes it possible to reduce the stresses experienced by the locks 64 and 65 in their respective notches 63 of the driver 62 and to ensure their release from the notches 63 when the coupling device 210 is tilted between the coupled and uncoupled configurations.

[0110] When the coupling device 210 is in a decoupled configuration, the eccentric 56 is not subject to the rotation of the main shaft 32. In this configuration, the output levers 42 and 44 are held in a fixed position relative to the frame 22. To ensure that the output levers 42 and 44 remain in a fixed position, the eccentric 56 includes retaining means, and the ratchet R includes locking means. The locking means are configured to engage with the retaining means when the coupling device is in the decoupled configuration so as to maintain the angular position of the eccentric 56. Maintaining the angular position of the eccentric 56 in the decoupled configuration of the coupling device allows the output levers 42 and 44, and therefore the frame of runners 2 controlled by subassembly 200', to remain in a fixed position.

[0111] As illustrated on the figure 4 , the eccentric 56 includes two restraint means cooperating with two immobilization means of the rat net R.

[0112] The eccentric 56 extends laterally by a plate 58. The plate 58 is secured by riveting to the side 571 of the cylindrical element 57 of the eccentric 56. A clamping surface 581 is provided at the periphery of the plate 58.

[0113] Each oscillating lever 71 or 72 of the smoothing device 70 is capable of cooperating via its terminal beak 711, 721 with the clamping surface 581 of the plate 58. On the figure 4 The beak 711 of the oscillating lever 71 actuates the slide 68 and the beak 721 of the oscillating lever 72 cooperates with the clamping surface 581. After a 180-degree rotation of the eccentric 56, the beak 711 cooperates with the clamping surface 581 and the beak 721 actuates the slide 68.

[0114] Each oscillating lever 71, 72 is subjected to the action of a return spring 73. The spring 73 tends to return the terminal beak 711, 721 opposite the plate 58 in the engagement position with the clamping surface 581 when the coupling device is in the decoupled configuration.

[0115] When the beak 711, 721 of the oscillating lever 71, 72 cooperates with the clamping surface 581 of the plate 58, the plate 58 is angularly immobilized, resulting in the angular immobilization of the eccentric 56.

[0116] In other words, a first restraining means formed by the clamping surface 581 of the plate 58 of the eccentric 56 cooperates with a first immobilizing means formed by the oscillating levers 71, 72 of the smoothing device 70 of the first actuating rod 52.

[0117] The oscillating levers 71, 72 of the smoothing device 70 also allow the coupling device 210 to be selectively actuated between the decoupled configuration and the coupled configuration in the stop position of the eccentric 56.

[0118] Advantageously, the oscillating levers 71, 72 are means of immobilization combining the selection and immobilization functions of the eccentric.

[0119] The first restraint means and the first immobilization means are centered on the same plane P5 perpendicular to the main axis X32 as the coupling device 210.

[0120] The cylindrical element 57 of the eccentric 56 includes an internal chamber 575 visible on the insert B of the figure 4 , by tearing. Along the main axis X32, the internal chamber 575 is arranged between the two flanks 571 and 572.

[0121] The internal chamber 575 includes an opening on the external peripheral surface 573 of the cylindrical element 57.

[0122] The internal chamber 575, for example, has a wavy shape consisting of two rounded openings 575A, 575B and a central groove 575C.

[0123] The internal chamber 575 is configured to at least partially accommodate an intermediate tray 84.

[0124] The intermediate plate 84 includes two tabs adapted to be positioned respectively in each rounded opening 575A, 575B of the internal chamber 575. The intermediate plate 84 is secured by riveting, for example by two rivets, to the side of the eccentric 572 located opposite the second actuating rod 54.

[0125] The intermediate plate 84 includes a free edge 84A opposite the legs and located outside the internal chamber 575. The free edge 84A of the intermediate plate 84 includes a clamping surface 841 provided at the periphery of the free edge 84A.

[0126] Advantageously, since the coupling device 210 is shared between the first blade 202 and the second blade 204, an inter-space between the first actuating rod 52 and the second actuating rod 54 is available.

[0127] This interspace allows the passage of locking levers 86 and 87. The locking levers 86 and 87 are placed on the front surface 54B of the second actuating rod 54.

[0128] The locking lever 86 is visible on insert B of the figure 4 , by pulling. The locking lever 87 is located behind the oscillating lever in the representation of the figure 4 .

[0129] The locking levers 86 and 87 are structurally identical to the oscillating levers 71,72 of the smoothing device 70 but do not perform any actuation function.

[0130] The locking levers 86 and 87 each include a terminal beak with a shape complementary to the clamping surface 841 of the intermediate plate 84; only the terminal beak 861 of the locking lever 86 is visible on insert B of the figure 4 by tearing. Under the action of a return spring 88, the terminal beak 861 opposite the intermediate plate 84 cooperates with the clamping surface 841 to maintain the angular position of the eccentric 56.

[0131] In other words, a second restraint means formed by the clamping surface 841 of the intermediate plate 84 of the eccentric 56 cooperates with a second immobilization means formed by the immobilization levers 86, 87.

[0132] These second means of restraint and immobilization are centered on a third plane P3 perpendicular to the main axis X32. The plane P3 is located between the first plane P2 defined by the first blade 202 and the second plane P4 defined by the second blade 204.

[0133] Advantageously, the drive device 206 for twin blades 202, 204 benefits from a second retaining means and a second immobilizing means. These second retaining and immobilizing means are additional compared to the drive device for a single blade 200.

[0134] In the second embodiment shown in the figure 7 Elements analogous to those of the first embodiment bear the same references. If a reference is used later in the description without being shown on the figure 7 or focused on the figure 7 Although not mentioned in the description, it refers to the same element as the one bearing the same reference in the first embodiment. The following primarily describes what distinguishes this second embodiment from the first.

[0135] In the second embodiment, the eccentric 56 comprises a single retaining means cooperating with a single immobilizing means of the rat net R.

[0136] In this second embodiment, the oscillating levers 71 and 72 only serve a selection function. They do not constitute a means of immobilization.

[0137] The eccentric 56 carries two lugs 91 provided with teeth 92 intended to engage with corresponding teeth 93 provided at the free end of an arm 94 mounted pivoting around an axis X94 on the first actuating rod 52 and subjected to the action of elastic means, for example a return spring 96 tending to return the teeth 93 into contact with the teeth 92 of the lugs 91. The arm 94 constitutes a means of immobilization.

[0138] The lugs 91 and the arm 94 engage under the action of the return spring 96 when the eccentric 56 is in one of its two diametrically opposed stopping positions. The lugs 91 and the arm 94 are centered on plane P5.

[0139] In an alternative not shown, the restraint means are subject to the action of a return spring which tends to return the restraint means into engagement with immobilization means.

[0140] The legs 91 are a means for retaining the eccentric 56, and the arm 94 is a means for immobilizing it. The retaining and immobilizing means are centered on the same plane P5, perpendicular to the central axis X32, as the coupling device 210.

[0141] In this second embodiment, a slot 424 passing through each lever 42, 44 is provided, defining a material bridge that extends over a peripheral angular sector of the shaft 34 and is centered on the axis X34. The slot 424 allows the rolling elements of the lever 42, 44 joint to be relieved around the axis X34, in a manner analogous to the inner ring bearing slots introduced in FR1912808.

[0142] Advantageously, in both embodiments of the invention mentioned above, the connecting rod 16 has an adjustable length thanks to the adjustment device shown in the figure 9 The connecting rod 16 extends along a first connecting rod axis X16.

[0143] The connecting rod 16 comprises two flanges 170A and 170B mounted on a joint 169 carried by the clip 18. The two flanges 170A and 170B are fixed to a bar 172. The bar 172 is generally parallelepiped in shape. The bar 172 includes, at one end 172A positioned on the side of the clip 18, a hook 172B. The second end of the bar 172 is inserted into a hollow tube 174. The hollow tube 174 forms the body of the connecting rod 16. The hollow tube 174 also receives a rod 176. The rod 176 is held in the hollow tube 174 by means of retaining screws 177. The rod 176 includes, at one end located outside the hollow tube 174, a hook 176A. The length adjustment of the connecting rod 16 is determined by the distance between the hook 172B of the bar 172 and the hook 176A of the rod 176, measured along the first axis of the connecting rod X16.

[0144] Advantageously, in both embodiments of the invention mentioned above, the connecting rods 162, 164 are also adjustable in length by means of adjustment devices shown in the figure 9 and identical to the connecting rod adjustment device 16.

[0145] The connecting rod 162 comprises flanges 232A and 232B mounted on a joint 222 carried by the clip 182. The two flanges 232A and 232B are riveted to a bar 242. The bar 242 includes a hook 242B at one end 242A. The other end of the bar 242 is inserted into a hollow tube 252 forming the body of the connecting rod 162. The hollow tube 252 also receives a rod 262. The rod 262 is held in the hollow tube 252 by means of retaining screws 272. The rod 262 includes, at one end located outside the hollow tube 252, a hook 262A. The connecting rod 164 comprises flanges 234A and 234B mounted on a joint 224 carried by the clip 184. The two flanges 234A and 234B are riveted to a bar 244. The bar 244 includes a hook 244B at one end 244A. The other end of the bar 244 is inserted into a hollow tube 254 forming the body of the connecting rod 164. The hollow tube 254 also receives a rod 264.The rod 264 is held in the hollow tube 254 by means of retaining screws 274. The rod 264 includes, at one end located outside the hollow tube 254, a hook 264A.

[0146] To ensure optimal vertical movement of the rail frame 2, it is necessary that the length of the two connecting rods 162 and 164 be identical. Thus, the hooks 242B and 244B are configured to simultaneously receive one end of a connecting rod length adjustment tool, and the hooks 262A and 264A are configured to simultaneously receive the second end of a connecting rod length adjustment tool. The distance between the first and second ends of the tool can be adjusted manually, in particular by means of a screw compass-type system in which the gap between the ends of the tool is manually adjusted by rotating a screw in one or the opposite direction. In other words, the connecting rod length adjustment tool simultaneously rests on both pairs of hooks 242B, 244B and 262A, 264A to ensure equal adjustment between the two connecting rods 162 and 164.

[0147] According to an unrepresented embodiment of the invention, legs and an arm comparable to the second embodiment are centered and cooperate in the plane P3.

[0148] According to an unrepresented embodiment of the invention, eccentric retention means and associated immobilization means are doubled and centered both in plane P3 and in plane P5.

[0149] According to an embodiment of the invention not shown, the first actuating rod 52 and the second actuating rod 54 have different geometries. In particular, the second actuating rod 54 has a larger diameter opening than the diameter of the opening of the first actuating rod 52. The cylindrical element 57 of the eccentric 56 of the drive device has a shoulder on its outer peripheral surface 573 so as to cooperate with the third bearing contained in the opening of the second actuating rod 54. This variant allows for synchronized movement of the first and second output levers 42 and 44, but with a different amplitude, in particular a greater amplitude of movement of the second output lever 44.

[0150] Advantageously and in an embodiment not shown, the eccentric can define a fourth zone cooperating with a first zone of a third actuating rod and actuate three twin blades related to the same frame of runners 2. The corresponding blade is a triple blade.

[0151] According to yet another unrepresented variant, the number of paired blades within a subset can be strictly greater than three. In this case, the blade in question can be quadruple, quintuple, etc.

[0152] In practice, the number of single 200 blades and twin 200' blades of the R ratier is variable, depending on the armor to be made on the fabric T. It is advantageously between 4 and 20.

[0153] Insofar as it is technically feasible and is included within the scope defined by the claims, the embodiments and variants mentioned above may be combined with each other.

Claims

1. A rotary dobby (R) for a loom (M), the rotary dobby comprising: - a frame (22) ; - a main shaft (32) supported by the frame (22) and extending according to a main axis (X32); - an output lever shaft (34), supported by the frame (22) and extending according to a common axis (X34) parallel to the main axis (34); - at least one sub-assembly (200') formed by a first knife (202) and at least one second knife (204), mounted adjacent and respectively defining a first plane (P2) perpendicular to the main axis (X32) and a second plane (P4) perpendicular to the main axis (X32), the sub-assembly comprising : • a first output lever (42) belonging to the first knife (202) and a second output lever (44) belonging to the second knife (204), the first (42) and second (44) output levers being adjacent along the common axis (X34), mounted, movable in rotation, about the output lever shaft (34) and driven in a reciprocating movement during weaving; • a first actuating rod (52) belonging to the first knife (202), coupled to the first output lever (42) and mounted, movable in rotation about the main shaft (32); • a second actuating rod (54) belonging to the second knife (204), coupled to the second output lever (44) and mounted, movable in rotation about the main shaft (32); • an eccentric (56) mounted about the main shaft (32) and comprising: ∘ a first zone (56A) configured to cooperate with a first zone (52A) of the first actuating rod (52) constituting a first articulation, by means of which the eccentric (56) and the first actuating rod (52) are pivotable relative to each other about a first axis (X1) parallel to the main axis (X32); ∘ a second zone (56B) configured to cooperate with a guide ring (59) carried by the main shaft (32), constituting a second articulation, by means of which the eccentric (56) and the main shaft (32) are pivotable relative to each other about the main axis (X32); • a coupling device (210), able to selectively secure, in rotation, the main shaft (32) and the eccentric (56) in a coupled configuration of the coupling device (210), and leaving the eccentric (56) free to rotate relative to the main shaft (32) in an uncoupled configuration of the coupling device (210), characterized in that the eccentric (56) comprises a third zone (56C) configured to cooperate with a first zone (54A) of the second actuating rod (54) constituting a third articulation, by means of which the eccentric (56) and the second actuating rod (54) are pivotable relative to one another about the first axis (X1).

2. The rotary dobby according to claim 1, characterized in that the coupling device (210) comprises a driver (62) integral with the main shaft (32), and two latches (64, 65), articulated on the eccentric (56) and able to cooperate with the driver (62) in the coupled configuration of the coupling device (210) to secure, in rotation, the eccentric (56) and the main shaft (32) about the main axis (X32).

3. The rotary according to one of claims 1 and 2, characterized in that: - the first articulation comprises a first bearing (521, 522) interposed, radially to the first axis (X1), between the eccentric (56) and the first actuating rod (52); - the second articulation comprises a second bearing (591, 592) interposed, radially to the main axis (X32), between the eccentric (56) and the main shaft (32); - the third articulation comprises a third bearing (541, 542) interposed, radially to the first axis (X1), between the eccentric (56) and the second actuating rod (54).

4. The rotary dobby according to claim 3, characterized in that the second bearing (591, 592) comprises the rollers (592) which extend parallel to the main shaft (32), straddling the first plane (P2) and the second plane (P4).

5. The rotary dobby according to one of claims 3 or 4, characterized in that the eccentric (56) comprises a cylindrical element (57) which includes: - two shoulders (571, 572) spaced apart by an axial distance greater than an axial distance between the first plane (P2) and the second plane (P4), - an outer peripheral surface (573) which defines the first zone (56A) as a first ball race for the first bearing (521, 522) and the third zone (56C) as a third ball race for the third bearing (541, 542), - a bore (574) the interior surface of which defines the second zone (56B) as a second ball race for the second bearing (591, 592).

6. The rotary dobby according to any of the preceding claims, characterized in that the eccentric (56) comprises retaining means (58, 84, 91) and in that the dobby (R) comprises immobilization means (71, 72, 86, 87, 94) for the eccentric (56), the immobilization means (71, 72, 86, 87, 94) being configured to engage with the retaining means (58, 84, 91) when the coupling device (210) is in the uncoupled configuration or when the eccentric (56) is in a stop position about the main shaft (32).

7. The rotary dobby according to claim 6, characterized in that the first immobilization means (71, 72, 86, 87, 94) are mounted on a front surface (52B) of the first actuating rod (52) or on a front surface (54B) of the second actuating rod (54) and comprise elastic return means (73, 88, 96) configured to return into the engagement position the immobilization means (71, 72, 86, 87, 94) with the retaining means (58, 84, 91).

8. The rotary dobby according to one of claims 6 or 7, characterized in that it comprises second immobilization means (71, 72) able to selectively actuate the coupling device (210) between the uncoupled configuration and the coupled configuration in the stop position of the eccentric (56).

9. The rotary dobby according to one of claims 6 to 8, characterized in that a first retaining means (84) and a first immobilization means (86, 87) are centered on a third plane (P3) perpendicular to the main axis (X32) and located between the first plane (P2) and the second plane (P4).

10. The rotary dobby according to one of claims 6 to 9, characterized in that the coupling device (210) is centered on a fourth plane (P5) perpendicular to the main axis (X32) and in that a second retaining means (58, 91) and a second immobilization means (71, 72, 94) are centered on the fourth plane (P5).

11. The rotary dobby according to claims 9 and 10, characterized in that the first and / or the second retaining means (58, 84) comprise a plate (58, 84) centered on the third (P3) or fourth plane (P5) perpendicular to the main shaft (32) and riveted to a shoulder (571, 572) of the cylindrical element (57) of the eccentric (56).

12. The rotary dobby according to claims 5 and 11, characterized in that the cylindrical element (57) of the eccentric (56) comprises a chamber (575) arranged between the two shoulders (571, 572) of the cylindrical element (57), presenting an opening on the outer peripheral surface (573) of the cylindrical element (57) and configured to at least partially receive a plate (84) belonging to the first retaining means.

13. The rotary dobby according to any one of the preceding claims, characterized in that the dobby (R) comprises a modulator (36) configured to mechanically modulate the rotation (θ') of the main shaft (32) from the rotation (θ) of a drive shaft (40) of the dobby (R) and in that, during the continuous rotation (θ) of the drive shaft (40), the main shaft (32) performs a rotary movement (θ') marked by an alternating movement of amplitude (Δθ') at the stop position of the eccentric (56).

14. A loom comprising: - a rotary dobby (R) according to one of the preceding claims, - a drawing mechanism (4) for controlling a heald frame (2), this drawing mechanism comprising at least one set of connecting rods (102, 104, 142, 144), draw rods (162, 164) and return levers (122, 124) coupling the heald frame (2) to the first knife (202) and the second knife (204) and configured to return a reciprocating movement of the first output lever (42) and the second output lever (44) to the heald frame (2), the heald frame (2) having a reciprocating movement between a high position and a low position.

15. A weaving machine according to claim 14, characterized in that the drawing mechanism (4) comprises: - a first draw rod (162) coupled to the first output lever (42) of the first knife (202) and which drives at least one first return lever (122) to which a first connecting rod (102) is coupled to the frame, - a second draw rod (164) coupled to the second output lever (44) of the second knife (204), and which drives at least one second return lever (124) to which a second frame connecting rod (104), is coupled, and in that the first (102) and second (104) frame connecting rods are coupled to the same heald frame (2).

16. The weaving machine according to one of claims 14 and 15, characterized in that the drawing mechanism (4) comprises a first adjustable clip (182) and a second adjustable clip (184), respectively mounted on the first output lever (42) and the second output lever (44) of the dobby (R) and configured to ensure pivotal assembly and adjustment of the first output lever (42) and the second output lever (44) to the drawing mechanism (4), and in that the clips (182, 184) are secured to one another.

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