FR2886951A1 - Weft yarn insertion device for weaving shed, has reed comprising attachments, distributed in two series along reed width of loom, guiding flexible parts of rapiers such that parts do not contact teeth of reed - Google Patents

Abstract

The device has wheels (21, 22) rotating around axes (A 21, A 22) with respect to a frame of a loom. An assembly forms a reed comprising attachments (133, 136) that are distributed in two series (S 1, S 2) along a reed width of the loom. The attachments are provided for guiding flexible parts (112, 122) of rapiers such that the parts (112, 122) do not contact the teeth (132a) of a reed (132). The reed is situated between a plane containing points and a plane perpendicular to fabric plies before the separation of the plies. An independent claim is also included for a loom to be woven comprising a weft yarn insertion device.

Description

The invention relates to a device for inserting a weft thread for a

  craft with two superposed sheets, and a loom equipped with such a device.

  In the field of looms with two superposed layers, sometimes referred to as double loom, it is known, for example from FR-A2552455, to insert the weft son in crowds defined by the trade by means of rigid lances with the heads are guided, on the one hand, by pieces integral with the comb of the craft and, on the other hand, by the comb. These rigid lances have such inertia that their respective drive means must be able to develop significant power, which makes them expensive.

  It is also known from DE-A-41 31 745 to use lances comprising a head or claw for driving the weft threads and a part provided with openings in which the teeth of a wheel driven by a displaced motor mesh. by a training comb of the trade. The engines reported on the comb substantially increase the inertia of the wing, which limits the speed of operation of the craft.

  In these known materials, the guide means provided in the vicinity of the comb are capable of interacting only with the claws of the lances, which means that, in the case of looms of large lambing width, the lances are guided only on a small part of their length when fully deployed. They must therefore have a relatively high rigidity, which is penalizing in terms of mass and inertia. In addition, these lances impose a significant lateral bulk for the craft.

  It is these drawbacks that the invention more particularly intends to remedy by proposing a weft insertion device for a loom with two superposed sheets through which the lances can be efficiently guided, while the inertia of the parts in movement can be optimized.

  With this in mind, the invention relates to a device for inserting weft yarns for a loom with two superposed layers, this device comprising flexible lances provided with weft-threading claws in a shed and a comb movable between a position. rear, compatible with the insertion of weft threads into the crowd, and a striking position. Each lance comprises a claw and a flexible part partially wound on a drive wheel, while each wheel rotates about a fixed axis relative to the frame of the loom and that the comb assembly is equipped with means, distributed according to the width of levee, guiding the flexible part of each lance. The guide means are divided into two series, a first series of which is connected to the comb in the vicinity of its upper part and the second series of which is connected to the comb in the vicinity of its lower part, the first series being dedicated to guiding the part flexible of the upper lance (s), while the second series is dedicated to guiding the flexible part of the lower lance (s). The guide means are able to guide the flexible parts of the lances without them interacting with the teeth of the comb.

  The lances can be effectively guided on most of their trajectory in the crowd through guiding means that interact not with the single claw of each lance, but with its flexible portion or ribbon that extends over most of this trajectory when the spear is fully engaged in a crowd. Since the drive wheel of the flexible portion of each lance is not driven by the comb assembly, this assembly is lighter and easier to drive. The distribution of the guide means in two distinct series allows to arrange the guide means so that the position of the trajectory of the lances in the crowd is optimized. Since the guiding means are sufficient to guide the flexible parts or strips of the lances alone, these flexible parts are not likely to wear in contact with the front edges of the teeth of the comb.

  With these known materials, the stroke of the comb must be sufficient so that, when the latter is in a rear configuration compatible with the introduction of a weft thread, the means for supporting the claws are arranged generally inside the crowd, whereas, in striking position, these guide means are arranged outside the crowd. This relatively important race requires in practice to increase the distance between the points of striking and the smooth closest to these points of striking. Such a rail can be mounted on a smooth frame or controlled by a Jacquard harness. However, the greater this distance, the longer the race of the pile yarns and warp threads is long, which induces significant stresses on the drive devices and in practice limits the speed of operation of a loom equipped with of these devices.

  In order to optimize the running of the pile and warp threads, it is expected that the comb, when in the rear position, is located entirely between a plane containing the striking points and a plane perpendicular to the sheets of cloth before their separation, this perpendicular plane passing, for each tooth of the comb, by a point located, relative to that of the points of the front edge of this tooth intended to bear against the points of striking which is furthest from these points of striking , at a distance equal to five times the width of the tooth at that particular point of its leading edge.

  Thanks to the shape of the comb, the distance between the impact points and the control strands of the pile and warp threads is minimized, which makes it possible to reduce the maximum strokes that the Jacquard machine has to print to the pile threads or that the fundamental armor mechanics must print to the warp threads.

  According to other advantageous but not mandatory aspects, such an insertion device may incorporate one or more of the following features: According to certain embodiments, the comb is generally curved, with its concavity oriented towards the points of impact, comb teeth each comprising two elongated portions and each centered on a longitudinal axis, said longitudinal axes forming between them an angle of between 15 and 45, preferably of the order of 30. In this case, the point of the leading edge of the tooth which is intended to abut against a striking point is defined in a junction zone between the elongate portions of a tooth, the perpendicular plane being situated beyond a concave portion of the trailing edge of each tooth at this area.

  According to another embodiment, the comb 25 may be substantially rectilinear.

  - The part of the comb which defines its maximum bulk at the opposite of the striking points, when the comb is in the rear position, extends in a direction generally perpendicular to the tissue plies when the comb is in this position, while a geometric plane comprising the points of the edges of the comb teeth intended to abut against the striking points is perpendicular to these plies when the comb is in the striking position. The aforementioned direction is advantageously inclined relative to the aforementioned plane, an angle which is preferably between 15 and 45.

  At least one of the guide means can also guide the claw of a lance in its movement back and forth.

  The axis of rotation of the drive wheel of the flexible part of each lance is inclined with respect to a plane parallel to the sheets of fabric before their separation at an angle of between 50 and 90, preferably between 60 and 80, more preferably of the order of 75. The particular orientation of the axis around which the drive wheels rotate allows these flexible parts to be set in motion with an orientation compatible with that of the comb when the latter is in the rear position.

  - The series of guide means are each formed by a succession of tabs distributed along the length of the comb and each defining a passage orifice of which at least a portion is substantially complementary in shape to that of the section of the flexible portion of the lance corresponding. In this case, at least one of the orifices may be provided with an opening for the passage of a junction part between the flexible part and the claw of a lance, such an opening being oriented towards the teeth of the comb. In addition, at least one of the orifices may have a generally cross-shaped shape, two branches of this cross being dedicated to guiding the flexible part of the corresponding rail, while the two other branches which are substantially perpendicular to the previous ones and whose one opens towards the comb, are dedicated to guide the claw of the lance and a junction portion between the claw and the flexible portion. It can also be provided that the tabs forming the guiding means of the flexible part of the upper lances or are supported by the comb, while the lugs forming the guide means of the flexible part of the lower lances or are supported at near the bottom of the comb. The tabs which form the guide means of the flexible part of the upper lances or can be supported by a cap covering all the teeth of the comb and, preferably, made by a metal section fixed on the upper ends of these teeth . The material used for the profile is preferably a light alloy, especially an aluminum-based alloy.

  - The comb and / or an integral member of the comb carries (s) crowd calibration means which, with respect to the upper crowd, may be formed by a portion of said cap.

  - The teeth of the comb are wider at their base than at their end farthest from the wing.

  The invention also relates to a loom with two superposed webs equipped with a weft thread insertion device as mentioned above.

  Such a loom is more economical, easier to install and adjust than trades of the state of the art. It can also operate at a higher speed.

  The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of three embodiments of a weft insertion device and a loom. in accordance with its principle, given solely by way of example and with reference to the accompanying drawings, in which: FIG. 1 is a basic section of a loom according to a first embodiment of the invention equipped with a weft insertion device according to the invention in a first operating position; FIG. 1A is a view on a larger scale of detail 1A in FIG. 1, the trace of the warp and healds being omitted for clarity of the drawing; - Figure 2 is a section similar to Figure 1, while the loom is in a second operating position; FIG. 3 is a perspective view of certain constituent elements of the device for inserting the loom of FIGS. 1 and 2; FIG. 4 is an enlarged view of only the guiding elements of the flexible parts of the lances; FIG. 5 is a view similar to FIG. 1A for a device according to a second embodiment of the invention and FIG. 6 is a partial view of the type of FIG. 5 but on a smaller scale, for a device according to a third embodiment of the invention.

  The loom M shown in FIGS. 1 and 2 is intended for the formation of two tissue plies N1 and N2, for example two belts T1 and T2 woven simultaneously and separated from each other by a knife 1 hair cutter carried by a carriage 2 and disposed downstream of two strike points P1r P2 to which converge respectively two F1r F2 crowds defined by the pile yarns 4 of the trade whose vertical movement is controlled by rails 3 actuated by a Jacquard harness as well as by chain son 4 'whose vertical movement is controlled by smooth mounted on smooth frames 3', themselves driven by a dobby or a cam mechanism not shown.

  We denote by 7E1 a median plane of the plies N1 and N2 between the points P1 and P2 and their zone of separation by the knife 1. The plane 7t1 is, in practice, substantially horizontal.

  The weft threads 51 and 52 intended to constitute, with the corresponding warp threads, the plies N1 and N2 are inserted into the masses F1 and F2 by means of two lances 11 and 12 each comprising a head or claw 111, respectively 121, on which can be hung a weft thread 5, and a flexible strip 112, respectively 122, for driving the corresponding claw in the direction of two axes Y1r respectively Y2, parallel to each other and perpendicular to the son 4 and 4 ' and in the plane of Figure 1.

  An assembly 13 forming a comb and movable pivotally about an axis Y3 parallel to the axes Y1 and Y2 comprises a flapper 131 and a comb 132 consisting of a row of teeth mounted on the flapper 131 and driven by the latter. rotation around the Y3 axis. The teeth 132a of the combs 132 can thus be brought in abutment against the points P1 and Per as shown in FIG. 2, where the leaf 131 has been pivoted about the axis Y3, with respect to the position of FIG. means not shown and known per se.

  Each tooth 132a is defined between a leading edge 132b facing the striking points and a trailing edge 132c facing the rails 3.

  Consider the portion 132b1 of the front edge 132b which connects the points P'1 and P'2 of the edge 132b intended to abut against the strike points P1 and P2. 7Av is a plane containing the portions 132b1 of the front edges 132b of the different teeth of the comb 132. This plane is parallel to the insertion directions of the weft son in the crowds F1 and F2.

  132a1 is the portion of each tooth 132a further away from the wing 131 than the point P'1. As is more particularly apparent from FIG. 1, the portions 132a1 of the teeth 132 are generally rectilinear and delimit the maximum dimensions of the comb in the direction of the rails 3.

  The comb 132 is mounted on the leaf 131 through a rail 131a receiving the lower ends of the teeth 132a and immobilized by a wedge 131b held in place on the leaf 131 by means known per se and not shown, such as screws.

  To ensure a substantially rectilinear trajectory of the claw 111, the assembly 13 is equipped with a series S1 of lugs 133 distributed over substantially the entire length of the comb 132, that is to say, according to the loom width of the loom M, and integral with the comb 132. The tabs 133 are mounted in groups of three consoles 134, each bracket being fixed on a metal section 135 which is itself fixed on the upper ends of the teeth 132a, that is to say say on the ends of these teeth furthest away from the axis Y3. The profile 135 is made of light metal alloy, in particular based on aluminum.

  Each tab 133 is pierced with an orifice 133a comprising two extensions 133a1 and 133a2 of substantially complementary shapes of the upper and lower portions of the cross section of the strip 112, which makes it possible to obtain a guiding effect of the strip 112 which constitutes the part flexible lance 11, according to the width of the upper, as the claw 111 progresses towards the side of the comb 132 opposite that through which it enters the crowd. The shape of the orifices 133a thus makes it possible to guide the ribbon 112 without interaction or contact between the lance 11 and the teeth 132a, which prevents premature wear of the ribbon 112 or the claw 111 by friction against the front edges 132b of the teeth 132a.

  In Figure 4, the trace of the component parts of the lances 11 and 12 is shown in phantom.

  The orifice 133a also comprises a lateral extension 133a3.

  Similarly, a series S2 of tabs 136 is mounted on consoles 137 fixed to the leaf 131, each tab 136 having an orifice 136a whose two extensions 136a1 and 136a2 are complementary shapes of the upper and lower parts of the cross section of the ribbon 122, which effectively guides the ribbon 122, which is the flexible portion of the lance 12 engaged in the shed F2, without interaction with the comb 132. An additional extension 136a3 is provided, similarly to the extension 133a3 of the orifice 133.

  The orifices 133a and 136a are open towards the comb 132. More specifically, they each define an opening or slot 133b, respectively 136b, in which a joining portion 113 of the claw 111 may slide with the ribbon 112 or a portion 123 of junction of the claw 121 with the ribbon 122. The portions 113 and 123 extend respectively into the extensions 133a3 and 136a3. Thus, the extensions 133a3 and 136a3 and the openings or slots 133b and 136b make it possible to guide the claws 111 and 121, through the parts 113 and 123, in their movement back and forth during the insertion of the weft son.

  In other words, the overall cross shape of the orifices 133a and 136a serves to guide both the claws 111 and 121, the ribbons 112 and 122 and the parts 113 and 123. The extensions 133a1 and 133a2 form two branches of the cross 133a 133a3 of the opening and the opening 133b form two other branches perpendicular to the previous. It is the same for the portions of the opening 136b. As a variant, only certain orifices 133a and 136b have this cross shape.

  In the configuration of Figure 2, the tabs 133 and 136 are located outside the crowds, so that they do not risk interfering points P1 and P2.

  To allow the movement of the lances 11 and 12 in the direction of the axes Y1 and Y2, two gears 21 and 22 are supported by the frame 50 of the loom and provided with teeth 211, respectively 221, able to be engaged in openings 114, respectively 124, formed in the ribbons 112 and 122. The ribbons 112 and 122 are partially wound on the wheels 21 and 22, the portions of the ribbons 112 and 122 located on either side of the wheels 21 and 22 being not parallel. As the ribbons are wound about 90 on the wheels, their portions in question are substantially perpendicular. Of course, another winding angle of the ribbons can be chosen, preferably in a range between 30 and 180.

  A21 denotes the geometric axis of rotation of the wheel 21. A22 denotes the geometric axis of rotation of the wheel 22. The axes A21 and A22 are fixed with respect to the frame 50. In the example represented, the axes A21 and A22 are merged. This is however not mandatory, the axes A21 and A22 may not even be parallel.

  As shown in phantom only in FIG. 3, guide means 31 and 32 are respectively provided for the ribbons 112 and 122, on the one hand between the wheels 21 and 22 and the comb 132, on the other hand between the wheels and the ends of the ribbons opposite their claws.

  The wheels 21 and 22 must drive the ribbons 112 and 122 when the assembly 13 is in the position of Figure 1 in which the orifices 133a and 136a are respectively opposite the insertion areas of the weft son in the flounder Fl2 .

  Z is the area of the loom located upstream of the comb 132 in the configuration of Figure 1, the rails 3 driven by the Jacquard harness and the smooth driven by the frames 3 'being arranged in this zone Z. We note the distance , taken parallel to the plane 7Z1r between, on the one hand, a plane 7E2 containing the striking points P1 and P2 and, on the other hand, the zone Z. The comb 132 is curved, with its concavity turned towards the points P1 and P2. More specifically, the teeth 132a are divided into two elongated portions 132a1 and 132a2, substantially rectilinear, each centered on a longitudinal axis B1 or B2 and meeting in a connection zone 132a3. The axes B1 and B2 form between them an angle (3 of the order of 30. In practice, the angle R may be chosen between 15 and 45.

  Furthermore, the axes A21 and A22 are inclined with respect to the plane 7t1 by an angle α of the order of 75, so that the lances 11 and 12 can be driven into the succession of orifices 133a, respectively 136a, in the configuration of Figure 1, while the comb 132 is bent, as indicated above, and that the tabs 133 and 136 can be disposed outside the F1 and F2 crowds in the configuration of Figure 2. In In practice, the angle α may have a value of between 50 and 90, preferably between 70 and 80.

  The orientation of the openings 133b and 136b towards the teeth of the loom corresponds to the construction of the junction between the claws and the ribbons. It allows to obtain a small footprint of each spear, formed of a claw and a ribbon, in the crowd.

  Among the points P'1 and P'2, the point P'1 of each tooth 132a is farthest from the plane 7E2 when the comb is in the rear position. 1132 is the width of a tooth 132a taken parallel to the plane Z1 Z1 at its point P '1. It defines a plane? G3 parallel to the plane 7t2r that is to say perpendicular to the N1 and N2 tissue plies and passing 10 by a point Q1 located at a distance from the point P '1, taken parallel to the plane n1r equal to twice the value of the width 1132.

  Given its geometry, the comb 132 is located entirely between the planes n2 and L3 when in its rear position shown in Figures 1 and 1A. This makes it possible to minimize the distance d between the striking points P1 and P2 and the zone Z and to consequently reduce the maximum strokes of the control strands of the pile yarns and the warp yarns.

  In practice, the distance of can be chosen with a value less than or equal to five times the width 1132r, preferably three times this width.

  In all cases, the plane L3 extends beyond the convex portion 132c3 of the trailing edge 132c of each tooth 132a corresponding to the junction zone 132a3.

  When the comb is in the rear position, some son 4 chain or hair of the upper crowd F1 which are the only ones shown in Figure 1A, abut against a portion 135a of the section 135 treated for this purpose. Similarly, some son 4 of the chain or pile of the lower crowd F2, which are also the only ones shown in Figure lA, abut against an edge 131c of the rail 131a treated for this purpose. The portion 135a and the edge 131c, which are integral with the comb 132, used to calibrate the crowd by determining its overall height. The length of the teeth 132a can thus be reduced, which reduces the inertia of the wing 131 and the parts it moves.

  The width of a tooth 132a is noted in its portion 132a1, this width being taken perpendicularly to the axis B1. Similarly, 132 is the width, taken perpendicular to the axis B2, of a tooth 132a in its part 132a2. The value of 132 is greater than that of 1'132, which corresponds to the fact that the teeth 132a are wider at their base near the wing 131 than at their end farthest from the wing. This takes into account that the teeth 132a are more stressed at their base, their profile is thus otpimisé.

  In the second embodiment shown in FIG. 5, elements similar to those of the first embodiment bear identical references. Legs 133 and 136 allow the lances of the lances to be guided over the lug width. This embodiment differs from the previous one in that the comb 132 is generally rectilinear, the teeth 132a being defined between a front edge 132b and a rear edge 132c generally rectilinear and parallel, except at a portion 132b1 of the edge 132b which passes by the points P'1 and P'2 intended to bear against the strike points of the trade. The central axes B1 and B2 of the portions 132a1 and 132a2 of the teeth 132a are parallel. The part 132b1 makes it possible to define a plane ltAv which forms an angle 8 of the order of 45 with the axes B1 and B2. As before, a plane 7t3 is defined perpendicular to the tissue plies before their separation and passing through a point Q1 whose distance of, taken parallel to a% Z1 plane defined as in the first embodiment, is equal to twice the width 1132 of the tooth 132 at the point P'1. This value of d is, in practice, less than five times that of 1132, preferably three times that width.

  As in the first embodiment, the comb 132 is, in the rear position, located completely between the plane of the striking points and the plane L3. This geometry of the teeth of the comb 132 also makes it possible to obtain a good compactness, which limits the strokes necessary for the warp threads and the bristles.

  As shown in FIG. 6, the axes B1 and B2 of the rectilinear portions 132a1 and 132a2 of the teeth 132a of a comb 132 may form between them an angle (3 such that the portion of the teeth 132a that is furthest from the striking points is the part 132c3 of the trailing edge 132c, at the junction zone 132a3 between the parts 132a1 and 132a2.

  In the rear position shown in Figure 6, the assembly of the comb 132 is located between the striking points and a plane L3 defined as in the first two embodiments.

  As in these first two embodiments, tabs 133 and 136 serve to guide the lances of the lances to the lop width.

  The invention has been described with reference to figures in which only two lances are shown as equipping the loom. Such a configuration is possible. However, the craft advantageously comprises two upper lances and two lower lances, the upper lances joining from the sides of the crowds in the center of the upper crowd F1r while the lower lances meet in the center of the lower crowd F2. The weft thread then moves from one claw to another. The guide lugs 133 and 136 are then distributed, according to the width of lee, in two groups intended to guide respectively the lances introduced by one side of the crowds and those introduced by the other side.

  The invention has been shown with a mobile comb pivoting about the axis Y3. It also applies to looms equipped with a comb with a substantially parallel translation movement, the shape of the comb then being adapted. In this case, the two points of the front edge of each tooth intended to hit the strike points are at the same distance from these striking points. A plane equivalent to the plane 7t3 mentioned above can be defined at one or other of these particular points of the teeth.

Claims (1)

17 CLAIMS   1. Apparatus for inserting weft threads for a loom with two superposed webs, said device comprising: lances (11, 12) provided with claws (111, 121) for driving weft yarn in a crowd (FI, F2) and a comb (132) movable between a rear position (FIG. 1), compatible with the insertion of weft thread into the shed, and a striking position (FIG. 2), characterized in that: each lance comprises a claw (111, 121) and a flexible portion (112, 122) partially wound on a drive wheel (21, 22), in that each wheel (21, 22) rotates about an axis (A21 , A22) fixed relative to the frame (50) of the loom, - in that said comb assembly (13) is equipped with means (133, 136), distributed according to the width of the lug, for guiding the flexible part ( 112, 122) of each lance (11, 12), in that said guide means (133, 136) are divided into two series (S1, S2), of which a first series (S1) is connected to said comb in the vicinity of its upper portion (132a1) and whose second series (S2) is connected to said comb in the vicinity of its lower portion (132a2), the first series being dedicated to guiding the flexible portion (112) of the one or more upper lance (s) (11), while the second series is dedicated to guiding the flexible part (122) of the lower lance (s) 12 and - in that the guide means (133, 136) are capable of guiding said flexible portions (112, 122) without these interacting with the teeth (132a) of said comb (132).   2. Device according to claim 1, characterized in that, in the rear position, the comb (132) is located entirely between a plane (7t2) containing the strike points (P1r P2) and a plane (7t3) perpendicular to the layers (N1r N2) tissue prior to their separation (1), said perpendicular plane passing, for each tooth (132a) of said comb, by a point (Q1) located, relative to that (P'1) points (P'1r) P'2) of the front edge (132b) of said tooth intended to abut against the striking points (P1r P2) which is furthest from the corresponding striking point (P'1), at a distance (of) equal to five times the width (1132) of said tooth at said point (P '1) of its front edge.   3. Device according to one of the preceding claims, characterized in that said comb (132) is generally curved, with its concavity facing the strike points (P1r P2), the teeth (132a) of said comb comprising two parts (132a1 , 132a2) elongate and each centered on a longitudinal axis (B1, B2), said axes forming between them an angle ((3) between 15 and 45, preferably of the order of 30.   4. Device according to claims 2 and 3, characterized in that said point (P'1) intended to bear against a striking point is defined in a zone (132a3) junction between said elongate portions (132a1, 132a2 ), said perpendicular plane (? L3) being located beyond a convex portion (132c3) of the trailing edge (132c) of each tooth, at said area.   5. Device according to one of claims 1 or 2, characterized in that said comb (132) is substantially rectilinear.   6. Device according to one of the claims   previous, characterized in that the upper part (132a1) of said comb (132), which defines the maximum bulk of said comb opposite the strike points (P1r P2) when said comb is in the rear position, extends according to a direction (B1) generally perpendicular to the tissue plies (N1r N2) when said comb (132) is in the rear position, while a geometric plane (7LAv) comprising the points (P'1, P'2) of the edges ( 132b1) teeth (132a) of said comb intended to bear against the impact points (P1r P2) is perpendicular to said plies when said comb is in the striking position.   7. Device according to claim 2, characterized in that said direction (B1) is inclined relative to said plane (ltAv) of an angle (8) which is preferably between 15 and 45.   8. Device according to one of the preceding claims, characterized in that at least one of said guide means (133, 136) is adapted to guide also the claw (111, 113, 121, 123) of a lance ( 11, 12) in its movements back and forth.   9. Device according to one of the preceding claims, characterized in that the axis (A21, A22) of rotation of said wheel (21, 22) is inclined relative to a plane (7t1) parallel to the plies (N1r N2). ) of tissue before separation (1), an angle (a) between 50 and 90, preferably between 70 and 80, more preferably of the order of 75.   10. Device according to one of the preceding claims, characterized in that said series (S1r S2) of guide means are each formed by a succession of tabs (133, 136) distributed along the length of said comb (132) and defining each a passage opening (133a, 136a), of which at least one part (133a1, 133a2, 136a1, 136a2) is substantially complementary in shape to that of the section of the flexible part (112, 122) of the corresponding lance (11, 12).   11. Device according to claim 10, characterized in that at least one of said orifices (133a, 136a) is provided with an opening (133b, 136b) for passage of a portion (113, 123) of junction between the flexible portion (112, 122) and the claw (111, 121) of a lance (11, 12), said opening being oriented towards the teeth (132a) of said comb (132).   12. Device according to one of claims 10 or 11, characterized in that at least one of said orifices (133a, 136a) has a generally cross-shaped (133a1, 133a2, 133a3, 133b, 136a1, 136a2, 136a3, 136b), two branches (133a1, 133a2, 136a3, 136a2) of said cross being dedicated to guide the flexible portion (112, 122) of the corresponding lance (11, 12), while the other two branches (133a3, 133b 136a3, 136b) of said cross, substantially perpendicular to the preceding ones and one of which (133b, 136b) opens out towards said comb (132), are dedicated to guiding the claw (111, 121) of the lance (11). , 12) and a portion (113, 123) of junction between said claw and said flexible portion of said lance.   13. Device according to one of claims 10 to   12, characterized in that said tabs (133) forming the guide means of the flexible part (112) of the upper lance (s) (s) (11) are supported by an element (135) attached to the part upper (132a1) of said comb (132), while the tabs (136) forming the guide means of the flexible portion (122) of the lower lance (s) (s) (12) are supported in the vicinity of the lower part (132a2) of said comb.   14. Device according to claim 13, characterized in that said tabs (133) forming the guide means of the flexible part (112) of the upper lance (s) (s) (11) are supported by a cap ( 135) covering all the teeth (132a) of said comb (132).   15. Device according to claim 14, characterized in that said cap is formed by a metal section (135), preferably of light alloy, fixed on the upper ends of said teeth (132a).   16. Device according to one of the preceding claims, characterized in that said comb (132) and / or a member (131) integral with said comb carries (s) means (131a, 135) for calibrating the crowd (F1, F2).   17. Device according to one of claims 14 and and according to claim 16, characterized in that said cap (135) comprises a portion (135a) of calibration of the upper crowd (F1).   18. Device according to one of the claims   previous, characterized in that the teeth (132a) of said comb are wider (132/132) at their base (132a2) than at their end (132a1) furthest from the leaf ( 131) for driving said comb.   19. Loom with two superposed sheets (N1r N2) equipped with a weft insertion device (10-32) according to one of the preceding claims.