Dropwire transfer module and drawing-in machine comprising such a transfer module

Abstract

A dropwire transfer module includes a casing (40), an abutment part (50) movable relative to the casing, parallel to a transfer direction (D12), and forming an abutment surface (S50), an actuator, a clamping device including a first lever (66) and a carriage (62) forming a clamping surface (S62). The first lever (66) is configured to be reciprocally rotated relative to the casing (40) by the actuator, around a first rotation axis (Z1) fixed in position with respect to the casing (40). A rotational movement of the first lever (66) in a clamping rotation direction (R) causes a movement of the carriage into a disengaged position, where the clamping device (60) is completely offset of the abutment surface (S50) perpendicularly to the transfer direction (D12), an intermediate position, where the clamping surface (S62) cooperates with the abutment surface (S50) in the transfer direction (D12), with a dropwire (18a) in-between, the abutment part (50) being in the advanced position, and a final position, where the clamping surface (S62) and the abutment surface (S50) clamp the dropwire (18a) between them, the abutment part (50) being in the retracted position. At least on a portion of the movement of the carriage (62) between the disengaged position and the intermediate position, the carriage (62) follows a circular path located in a plane perpendicular to the first rotation axis (Z1).

Description

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a dropwire transfer module for a drawing-in machine. The present invention also relates to a drawing-in machine comprising, amongst others, a dropwire transfer module.

[0002] The present invention belongs to the technical field of drawing-in warp threads into dropwires of a loom.BACKGROUND OF THE INVENTION

[0003] Dropwires are used on looms for warp yarn breaking detection during weaving. Each dropwire is provided with a through-hole. On the loom, a warp yarn goes through the through-hole of each dropwire prior to reaching a shed forming zone of the loom.

[0004] During a drawing-in process, it is known to separate a dropwire from a stack of dropwires and to use a dropwire transport unit to move the separated dropwire into a threading position in which a warp yarn is inserted through the through-hole of the dropwire. Then, the dropwire is moved into one of several discharge positions in which the dropwire is transferred onto a receiving device, for instance a dropwire support rail.

[0005] WO00 / 1 1252A1 discloses a rotating dropwire transport unit with holding elements having each two sliders with coaxial movements along a clamping direction. The two sliders are configured to engage with a separated bent dropwire and to clamp it for its transport. The actuators of the two sliders must be mounted on a movable holding element of a rotating dropwire transport unit. This unit works satisfactorily but requires a lot of movable actuators.

[0006] On the other hand, WO9318215A1 discloses a dropwire transfer module with a pneumatic linear actuator driving a slide, which executes a two-stage movement. This system also works satisfactorily.

[0007] In these known systems, the actuators are linear actuators, which are relatively slow. Moreover, in these known systems, a clamping system of a slider can only have translational movements and, since the actuators are cylinders, there is no rigid connection between the cylinders and a casing of the dropwire transfer module. This might result in imprecise displacements of the dropwires.SUMMARY OF THE INVENTION

[0008] The purpose of the present invention is to avoid the drawbacks of the prior art with an improved dropwire transfer module capable of transferring more efficiently and more accurately a separated dropwire onto a holding element of a transport unit which can be of different types, for instance with a chain carrying holding elements, as known from FR2930950A, or with belts.

[0009] To this end, and according to a first aspect, the invention concerns a dropwire transfer module for a drawing-in machine, said dropwire transfer module including a casing; an abutment part movable relative to the casing, parallel to a transfer direction, between an advanced position and a retracted position, said abutment part forming an abutment surface; an actuator including a housing fixed with the casing and an actuation part movable with respect to the housing; a clamping device including a first lever and a carriage forming a clamping surface, the clamping surface and the abutment surface being configured to clamp a dropwire in-between. According to the invention, the first lever is configured to be reciprocally rotated relative to the casing by the actuation part of the actuator around a first rotation axis. The first rotation axis has a fixed position with respect to the casing and is transverse to the transfer direction. The first lever is connected to the carriage in such a way that a rotational movement of the first lever relative to the casing around the first rotation axis in a clamping rotation direction causes a movement of the carriage relative to the casing into at least the following successive positions ∘ a disengaged position, where the clamping device is completely offset of the abutment surface perpendicularly to the transfer direction; ∘ an intermediate position, where the clamping surface cooperates with the abutment surface in the transfer direction, with a dropwire in-between, the abutment part being in the advanced position ; ∘ a final position, where the clamping surface and the abutment surface clamp the dropwire between them, the abutment part being in the retracted position; Moreover, at least on a portion of the movement of the carriage between the disengaged position and the intermediate position, the carriage follows a circular path which is located in a plane perpendicular to the first rotation axis.

[0010] Thanks to the invention, the rotational movement of the first lever quickly and accurately drives the carriage in its movement from the disengaged position to the intermediate position and then to the final position, without needing the actuator to be mounted on a movable part such as a rotational head of a transport unit. Because a portion of this movement of the carriage between the disengaged position and the intermediate position follows a circular path, the movement is quicker than if it were made by successive translations. Besides a single actuator is used to drive the carriage through all positions.

[0011] According to advantageous but non-compulsory aspects of the invention, such a dropwire transfer module might incorporate one or several of the following features: The clamping device includes a rod articulated on the first lever around a second rotation axis and the rod supports the carriage. The clamping device includes a second lever rotatable relative to the casing around a third rotation axis having a fixed position with respect to the casing and the rod is articulated on the second lever around a fourth rotation axis. The clamping surface is parallel to the abutment surface. The first, second, third and fourth rotation axes are parallel. The casing, the first lever, the second lever and the rod form a deformable parallelogram structure having the first, second, third and fourth rotation axes as articulated corners. A third lever is articulated on the first lever, around a fifth rotation axis, angularly shifted, with respect to the second rotation axis, around the first rotation axis, and on the second lever, around a sixth rotation axis, angularly shifted, with respect to the fourth rotation axis, around the third rotation axis. The fifth rotation axis and the sixth rotation axis are parallel to the first rotation axis. The carriage is supported on the rod with only a possibility of relative translation along a direction perpendicular to the second rotation axis; the casing forms a guiding surface parallel to the transfer direction and the carriage comprises a contact surface configured to come into cooperation with the guiding surface when the first lever rotates around the first rotation axis in the clamping rotation direction for guiding the carriage in translation along the transfer direction, between the intermediate position and the final position. An elastic member interposed between the casing and the abutment part biases the abutment part in a forward direction parallel to the transfer direction toward the advanced position and, in the retracted position, the abutment part abuts, in a backward direction, against a stop formed by the casing. The actuation part of the actuator is an output shaft rotatable around the first rotation axis and the first lever is fast in rotation, around the first rotation axis, with the output shaft. An angular position of the output shaft around the first rotation axis, when the carriage is in the final position, is monitored by a sensor and a controller is configured to determine an information relating to the thickness of a dropwire located between the abutment surface and the clamping surface in the final position, based on a difference between the angular position monitored by the sensor and a reference position. The dropwire transfer module further comprises an obstacle mounted on the casing with a possibility of movement relative to the abutment part between ∘ a first position, where the obstacle cooperates with the abutment part in the retracted position and opposes a movement of the abutment part toward the advanced position; and ∘ a second position, where the obstacle does not oppose the movement of the abutment part from the retracted position to the advanced position. An elastic member biases the obstacle toward its first position. The clamping device comprises an actuating cam surface moved by the actuation part of the actuator and configured for moving the obstacle from its first position to its second position, when the carriage is in a position distant from the final position.

[0012] According to a second aspect, the invention concerns a drawing-in machine comprising a frame; a dropwire feeding unit supporting at least one stack of dropwires; a dropwire separation device configured to separate a front-most dropwire from the stack by putting it into a separated configuration, where a separating gap is formed between the front-most dropwire and the next dropwire of the stack; a dropwire transport unit with at least one holding element moved relative to the frame of the drawing-in machine along a transport path, which goes from a transport transfer position, where the separated dropwire is brought on the holding element, to one of several discharge positions, where the dropwire is discharged from the holding element onto a receiving device, via a transport threading position, where a warp yarn is inserted through the dropwire; a dropwire transfer module according to the invention for transferring a dropwire, from the separated configuration onto a holding element in the transport transfer position. Moreover, the casing of the dropwire transfer module is fixed with regard to the frame of the drawing-in machine.

[0013] According to advantageous but non-compulsory aspects of the invention, such a drawing-in machine might incorporate one or several of the following features: The abutment surface of the abutment part and the clamping surface of the carriage of the dropwire transfer module, in the final position of the carriage, are vertically offset from a holding element located in the transport transfer position. The plane, in which the circular path of the carriage moving between the disengaged position and the intermediate position is located, is a plane transverse to a median longitudinal plane of the stack, preferably a plane parallel to the transfer direction. The dropwire transfer module further comprises an ejection pusher movable with respect to the casing between an inactive position, where the ejection pusher does not interact with any dropwire carried by the dropwire transport unit, and an active position, where the ejection pusher pushes a dropwire away from a holding element. The clamping device comprises an ejection surface moved by the actuation part of the actuator and configured to come into cooperation with an ejection driving surface of the ejection pusher, to move the ejection pusher from its inactive position to its active position, when the first lever rotates with regard to the casing around the first rotation axis in an unclamping rotation direction opposite to the clamping rotation direction. The dropwire separation device comprises a separating knife configured to bend the front-most dropwire of the stack when the front-most dropwire is in its separated configuration, the dropwire feeding unit and the dropwire transport unit are located relative to one another such that, in its separated configuration, the separated front-most dropwire is partially in engagement with a pin of the holding element in the transport transfer position. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention will be better understood, based on the following description, which is given in correspondence with the appended figures and as an illustrative example, without restricting the object of the invention. In the annexed figures: Figure 1 is partial perspective view of a drawing-in machine according to the invention, this drawing-in machine incorporating a dropwire transfer module according to the invention, a carriage of the dropwire transfer module being in a disengaged position; Figure 2 shows, onto inserts A), B), two partly exploded views of the dropwire transfer module of the drawing-in machine of figure 1; Figure 3 is a partial cross-section along plane III on figure 1; Figure 4 is an enlarged partial cross-section along line IV-IV on figure 3; Figure 5 is an enlarged partial cross-section along line V-V on figure 3; Figure 6 is an enlarged partial cross-section along line VI-VI on figure 3; Figure 7 is a partial perspective view of the drawing-in machine when the carriage of the dropwire transfer module is in a first intermediate position; Figure 8 is a partial cross-section along plane VIII on figure 7; Figure 9 is a cross-section similar to figure 8 when the carriage is in a second intermediate position; Figure 10 shows, on insert A), a partial side view of the drawing-in machine and, on insert B), a partial cross-section along line X-X on insert A), when the carriage is in a final position; Figure 11 shows two inserts A) and B) similar to inserts A) and B) of figure 10, when the carriage is in a further position of releasing the dropwire; and Figure 12 shows two inserts A) and B) similar to inserts A) and B) of figures 10 and 11, upon ejection of a defective dropwire. DETAILED DESCRIPTION OF SOME EMBODIMENTS

[0015] Figure 1 shows a drawing-in machine 2 according to the invention. This drawing-in machine includes a frame 4, a dropwire feeding unit 6, a dropwire separation device 8, a dropwire transport unit 10 and a dropwire transfer module 12.

[0016] Axes X, Y and Z define an orthogonal reference frame attached to the frame 4 where axes X and Y are horizontal and axis Z is vertical.

[0017] The dropwire feeding unit 6 includes a support rail 14, which extends along a longitudinal axis A14 inclined with respect to the horizontal plane defined by axes X and Y.

[0018] In a non-represented variant, the support rail 14 can be horizontal.

[0019] The support rail 14 supports a stack 16 of dropwires 18. More precisely, the support rail 14 is engaged in an upper opening 19 of each dropwire 18.

[0020] P16 denotes a median longitudinal plane of the stack 16, which is parallel to the plane of figure 3 and to the longitudinal axis A14.

[0021] In the example of the figures, all dropwires building up the stack 16 are identical and 18a denotes the front-most dropwire 18, i.e. the dropwire which is the closest to the dropwire transport unit 10.

[0022] 18b denotes a first principal face of the front-most dropwire 17a, oriented toward the dropwire transport unit 10. 18c denotes a second principal face of the front-most dropwire 18a, opposite to the front principal face 18b and oriented toward the stack 16. The thickness of the dropwire 18a is measured between its two principal faces 18b and 18c.

[0023] The dropwire separation device 8 includes a casing 34 fixed with respect to the frame 4 of the drawing-in machine 2 and a separating knife 36 movable with respect to the casing 34, in translation along an actuation axis A36 which is non-parallel to the longitudinal axis A14 of the support rail 14. Advantageously, this axis A36 is parallel to the median longitudinal plane P16 and close to vertical.

[0024] The separating knife 36 has a head 36a configured to engage an upper edge 18d of the front-most dropwire 18a. The head 36a of the separating knife 36 is located next to one end of the support rail 14 and includes a slot which is complementary to the upper edge 18d of any dropwire 18 of the stack 16, in order to cooperate with only one dropwire upper edge 18d at a time. On the other hand, a bottom edge 18e of the front-most dropwire 18 is in abutment against a lower support member 38, fixed with respect to the frame 4 and which constitutes a stop for the front-most dropwire 18a. When it is actuated, the separating knife 36 exerts, on the front-most dropwire 18a, a downwardly oriented effort along the axis A36 in the direction of the lower support member 38. This results in bending this dropwire 18a, which comes in a separated configuration represented on figures 3 to 6, where the front-most dropwire 18a has a curved shape which brings it away, in a central region, from the next dropwire 18 which is flat.

[0025] A separating gap G18 is thus created between the second principal face 18c of the front-most dropwire 18a and the next dropwire 18 of the stack 16, as visible on figure 3.

[0026] The dropwire transfer module 12 is used to transfer, along a transfer direction D12, a front-most dropwire 18a in the separated configuration onto one holding element 24 in the transfer position, i.e. onto holding element 24a in the representation of the figures, and to repeat this transfer for successive dropwires 18 of the stack 16.

[0027] Advantageously and as visible on figure 3, the transfer direction D12 is close to horizontal, but slightly inclined, with respect to an horizontal plane P H parallel to the axes X and Y, by a non-zero angle α. Advantageously, the value of the angle α is between 1 and 10°, preferably equal to 5°.

[0028] Each holding element 24 includes an upper pin 30 and a lower pin 32 configured to be engaged within the upper opening 19 of a dropwire 18, when this dropwire is supported by this holding element.

[0029] Each lower pin 32 of a holding element 24 is fixed with respect to a main body of such a holding element, whereas each upper pin 30 is vertically movable, in a vertical direction parallel to axis Z, with respect to this body. As visible on figure 3, a spring 33 biases the upper pin 30 upwardly, in a direction away from the lower pin 32.

[0030] 24e denotes a front face of a holding element 24, from which the two pins 30 and 32 protrude outwardly.

[0031] The front face 24e of the holding element 24a in the transport transfer position faces the stack 16, in particular its front-most dropwire 18a, along the transfer direction D12. Along the transfer direction D12, the first principal face 18b of the front-most dropwire faces the front face 24e of the holding element 24a in the transport transfer position.

[0032] The dropwire transport unit 10 includes a first transport belt 20 and a second transport belt 22, these belts carrying several holding elements 24 along a transport path, which is globally rectangular when seen from above in the example of the figures.

[0033] According to the needs, the shape of the transport path of the dropwire transport unit 10 can be different from a rectangle, provided that it forms a closed loop.

[0034] 23 denotes a sub-frame of the transport unit 10. The sub-frame 23 is fixed with, and secured to, the frame 4 of the drawing-in machine 2.

[0035] The dropwire transport unit 10 includes an actuator 11 mounted on the sub-frame 23 for driving the belts 20 and 22 along the transport path, which allows moving the holding elements 24, and thus the dropwires 18 carried by the holding elements 24, from the transport transfer position, where a first holding element 24a is represented on figure 1, to a transport threading position, where a second holding element 24b is represented on this figure. In the transfer position, the holding element 24a is ready for receiving the front-most dropwire 18a of the stack 16. In the transport threading position, a non-represented warp yarn is inserted, by non-represented threading means, into a through-hole 26 of the dropwire 18 carried by the holding element 24b. From the transport threading position, the holding element 24 carrying the dropwire 18 is moved, by the belt 20 or 22 to which the holding element 24 is secured, into one of several discharge positions. One of these positions is represented with a third holding element 24c on figure 1, in alignment with a receiving device 28 of the drawing-in machine 2 formed by juxtaposed receiving rails, only one receiving rail being shown on figure 1. In each discharge position, the dropwire 18 carried by the holding element 24c can be discharged on the corresponding receiving device 28 by non-represented discharging means. In other words, in each discharge position, and depending on a drawing-in draft including how warp threads are to be drawn through the dropwires of a loom, a dropwire 18 can be transferred from the holding element 24c to the adjacent receiving device 28.

[0036] The dropwire transfer module 12 includes a casing 40, which is fixed with regard to the frame 4 of the drawing-in machine 2.

[0037] Advantageously, the casing 40 is fixed with, and secured to, the sub-frame 23, e.g. by screws, the head of one of these screws being visible on figure 3 and identified with reference 42.

[0038] The casing 40 supports a single rotary electric actuator 44.

[0039] For instance, the actuator 44 can be a servo motor.

[0040] The actuator 44 includes a non-represented stator mounted within a housing 44a of the actuator, the housing and the stator being fixed with the casing 40.

[0041] The actuator 44 also includes a non-represented rotor and an output shaft 44b fast in rotation with the rotor and driven by the rotor in rotation around a first rotation axis Z1, which, in the embodiment of the figures, is substantially vertical. In particular, the first rotation axis Z1 is transverse to the transfer direction D12, preferably perpendicular to the transfer direction D12. The first rotation axis Z1 is inclined with respect to a vertical plane by the same angle α as the one mentioned here above between the transfer direction D12 and the plane P H . The first rotation axis Z1 has a fixed position with respect to the casing 40.

[0042] The output shaft 44b is an actuation part of the actuator 44. It is movable with respect to the housing 44a.

[0043] Some screws 45 are used for securing the housing 44a of the actuator 44 to the casing 40. Some of these screws are partly visible on figure 2.

[0044] Advantageously, the actuator 44 is controlled by a controller 46.

[0045] The controller 46 may also control the dropwire transport unit 10, in particular the displacement of the belts 21 and 22 along the transport path.

[0046] The dropwire transfer module 12 also includes an abutment device 48, which includes an abutment part 50 and a rectilinear groove 52. The abutment part 50 is slidably movable relative to the casing 40, in translation within the rectilinear groove 52, along a longitudinal axis A52, between an advanced position represented on figures 1 and 3 to 9 and a retracted position represented on figures 10 and 11. The groove 52 guides the translation of the abutment part 50 along its longitudinal axis A52.

[0047] Advantageously, the longitudinal axis A52 is parallel to the transfer direction D12. Thus, the abutment part 50 moves in a forward direction from its advanced to its retracted positions along the transfer direction D12. Moreover, the axis Z1 is perpendicular to the longitudinal axis A52.

[0048] An elastic member 54, which is a spring in the example of the figures, biases the abutment part 50 towards its advanced position. Alternatively, the elastic member can be of another type, e.g. a block of elastic material.

[0049] The abutment part 50 includes an abutment head 50a and a stem 50b. The stem 50b is partially engaged within the groove 52 and extends parallel to the longitudinal axis A52. The head 50a forms an abutment surface S50 that is turned toward the forward direction along the transfer direction D12. In particular, the abutment surface S50 constantly faces the stack 16, in particular the first principal face 18b of the front-most dropwire 18a. Due to the cooperation of shapes between the stem 50b and the groove 52, the translation of the abutment part 50 between its advanced and retracted positions is guided by the casing 40. By convention, the front side of the abutment part 50 is defined by the abutment surface S50 and the rear side of the abutment part 50 is defined by its stem 50b. The abutment surface S50 delimits a facing volume V50 which extends perpendicularly to the abutment surface S50 in front of its surface, outside the abutment part 50. The facing volume V50 is a prism whose base is delimited by an external edge of the abutment surface S50 and which extends perpendicular to the abutment surface, in front of the abutment surface S50, up to the stack 16.

[0050] The abutment surface S50 is offset vertically, that is in a direction substantially parallel to the axis Z, with respect to the front face 24e of the holding element 24a present in the transport transfer position. In other terms, the abutment surface S50 is situated at a vertical level, which out the vertical space defined between the upper pin 30 and the lower pin 32.

[0051] The abutment surface S50 is perpendicular to the longitudinal axis A52, thus to the transfer direction D12.

[0052] As visible on figure 3, the longitudinal axis A52 is not exactly horizontal in order to take into account the orientation of the first principal face 18b of the front-most dropwire 18a in its separated configuration, which is bent. Advantageously, the orientation of the longitudinal axis A52 is chosen in order for the abutment surface S50 to be as parallel as possible to the portion of the principal face 18b which faces the abutment surface S50. For example, the longitudinal axis A52 is inclined with an angle α' between 1 and 10°, preferably equal to 5°, with regard to an horizontal plane P' H . The values of angles α and α' are advantageously the same.

[0053] In the advanced position of the abutment part 50, the abutment part 50, in particular its stem 50b, preferably lies against a stop 55 formed by the casing 40, which prevents further movement of the abutment part 50 in the forward direction along the longitudinal axis A52. In the advanced position, the abutment surface S50 is in contact with, or very close to, the front-most dropwire 18 in separated configuration. In the retracted position, the abutment surface S50 lies again a stop 56 formed by the casing 40. In other words, in the retracted position, the abutment part 50 abuts, in a backward direction opposite to the forward direction, against the stop, which prevents further movement of the abutment part 50 in the backward direction, along the longitudinal axis A52. In this retracted position, the abutment surface S50 is globally aligned, along a vertical direction, with the front face 24e of the holding element 24a in the transport transfer position and is globally at the same position as the holding element 24a along the axis Y.

[0054] The stem 50b is provided with a lateral recess 50c visible, for instance, on figure 4.

[0055] The abutment device 48 also includes an obstacle 58 rotatably mounted on the casing 40 and movable around a pivot axis A58. Advantageously, the pivot axis A58 is parallel to the first rotation axis Z1 and perpendicular to the plane of figure 4.

[0056] The obstacle 58 is rotatable relative to the casing 40 between a first position and a second position. In the first position represented on figure 10, a tip 58a of the obstacle 58 is engaged within the recess 50c of the abutment part 50 in retracted position and the obstacle 58 opposes a movement of the abutment part 50, along the longitudinal axis A52, from the retracted position to the advanced position. In the second position represented for instance in figure 4, the obstacle 58, including its tip 58a is completely out of the recess 50c and does not prevent a movement of the abutment part 50 towards its advanced position.

[0057] An elastic member, which is a spring 59 in the example of the figures, is arranged between the obstacle 58 and a portion of the casing 40. The spring 59 biases the tip 58a of the obstacle 58 toward the groove 52, i.e. into the recess 50c of the abutment part 50 when the abutment part 50 is in the retracted position. Alternatively, the elastic member can be of another type, e.g. a block of elastic material.

[0058] The dropwire transfer module 12 also includes a clamping device 60. The clamping device 60 includes a carriage 62 and an articulated structure 64. The carriage 62 can also be called "clamping carriage".

[0059] A62 denotes a longitudinal axis of the carriage 62, which is advantageously perpendicular to the transfer direction D12.

[0060] The articulated structure 64 includes a first lever 66 and a second lever 68. The first lever 66 is closer to the abutment surface S50 than the second lever 68, in particular along longitudinal axis A62.

[0061] The first lever 66 is articulated on the casing 40 around the first rotation axis Z1. The first lever 66 is fast, in rotation around the first rotation axis Z1, with the output shaft 44b of the actuator 44. In other words, the first lever 66 is driven in rotation, around the first rotation axis Z1 and with respect to the casing 40, by the output shaft 44b of the actuator 44. A bearing 67 mounted on the casing 40 guides the rotation of the output shaft 44b around the first rotation axis Z1. In other words, the movement of the actuation part of the actuator 44 relative to the casing 40 is guided by the casing 40. As the actuator 44 can drive its output shaft 44b in both directions of rotation, the first lever 66 is reciprocally rotated by this actuation part around the first axis Z1.

[0062] A first guiding support 70 is articulated on the first lever 66 and movable around a second rotation axis Z2 with respect to the first lever 66. The second rotation axis Z2 is parallel to the first rotation axis Z1 and has a fixed position with respect to first lever 66.

[0063] The second lever 68 is rotatably mounted on the casing 40 and movable relative to the casing 40 around a third rotation axis Z3 parallel to the first and second rotation axes Z1 and Z2 and having a fixed position with respect to the casing 40. A bearing 72 mounted on the casing 40 guides the rotation of the second lever 68 relative to the casing 40 around the third rotation axis Z3.

[0064] A second guiding support 74 is articulated on the second lever 68 and rotates with respect to this second lever 68 around a fourth rotation axis Z4 parallel to rotation axes Z1, Z2 and Z3 and having a fixed position with respect to the second lever 68.

[0065] The carriage 62 is mounted on the two guiding supports 70 and 74.

[0066] Advantageously, a rod 76 connects these two guiding supports, as visible on figures 2 and 5. The two guiding supports 70 and 74 and the rod 76 together form a subassembly. The rod 76 is articulated respectively on the first and second levers 66 and 68, around the second and fourth axes Z2 and Z4, via the first and second guiding supports 70 and 74. The distance between the second and fourth rotation axes Z2 and Z4 is set by the rod 76 and chosen equal to the distance between the first and third rotation axes Z1 and Z3. The rod 76 is part of the articulated structure 64.

[0067] Advantageously, an articulation shaft between the first guiding support 70 and the first lever 66 around the second rotation axis Z2 is formed by a first screwed assembly 78, which has its stem aligned on the second rotation axis Z2. Similarly, a screwed assembly 80 having its stem aligned on the fourth rotation axis Z4 is used as an articulation shaft to rotatably connect the second guiding support 74 to the second lever 68.

[0068] A plane P13 including the first and third rotation axes Z1 and Z3 is always parallel to a plane P24 including the second and fourth rotations axes Z2 and Z4. Planes P13 and P24 are parallel to the longitudinal axis A62. These fourth rotation axes Z1, Z2, Z3 and Z4 constitutes the four articulated corners of a deformable parallelogram formed by the articulated structure 64. The deformable parallelogram articulated structure 64 includes the casing 40, the two levers 66 and 68 and the rod 76. This deformable parallelogram articulated structure 64 is visible in a plane parallel to the transfer direction D12 and the longitudinal axis A62 of the carriage 62, i.e. the plane of figures 4, 5, 6, 8, 9 and 10B) to 12B).

[0069] The deformable parallelogram can deform by modification of the angle between the plane P13 and a plane including the first and second rotation axes Z1 and Z2 and modification of the distance between planes P13 and P24, while the distances between the first and second axes Z1 and Z2, between the first and third axes Z1 and Z3, between the second and fourth axes Z2 and Z4 and between the fourth and third axes Z4 and Z3 remain constant.

[0070] The first and second guiding supports 70 and 74 respectively delimit a first pair of external parallel guiding surfaces, 70a, 70b and a second pair of external parallel guiding surfaces 74a, 74b, on either side of each guiding support. The guiding surfaces 70a, 70b, 74a and 74b are parallel to the longitudinal axis A62 of the carriage 62.

[0071] The carriage 62 is in sliding engagement with the four guiding surfaces 70a, 70b, 74a, 74b.

[0072] The carriage 62 includes an armature 62a, a first side body 62b and a second side body 62c. The two side bodies 62b and 62c are connected by screws 62e, which cross the armature 62a.

[0073] The armature 62a is in sliding engagement with the guiding surfaces 70a and 74a, whereas the second side body 62c is in sliding engagement with the guiding surfaces 70b and 74b. Due to the cooperation of the armature 62a and the second side body 62c with the two pairs of guiding surfaces 70a, 70b, 74a, 74b, the only possible movement, between the carriage 62 and the subassembly formed of the two guiding supports 70 and 74 and of the rod 76, is a translational movement parallel to the guiding surfaces 70a, 70b, 74a, 74b and to the longitudinal axis A62. This relative movement is perpendicular to the second rotation axis Z2. This relative movement is also perpendicular to the transfer direction D12. Thus the armature 62a has no possibility of movement relative to the rod 76 along the transfer direction D12.

[0074] A clamping spring 81 is interposed between the second side body 62c and the second guiding support 74 and biases the carriage 62 toward a position of the carriage where the carriage 62 abuts against the first guiding support 70. In other words, the clamping spring biases the carriage 62 toward the separating gap G18 and toward the facing volume V50.

[0075] The articulated structure 64 also includes a third lever 82 articulated on the first lever 66, around a fifth rotation axis Z5, and on the second lever 68, around a sixth rotation axis Z6. The two rotation axes Z5 and Z6 are parallel to the rotation axes Z1, Z2, Z3 and Z4 and respectively have a fixed position with respect to the first lever 66 and to the second lever 68. The fifth rotation axis Z5 is angularly shifted, with regard to the second rotation axis Z2, around the first rotation axis Z1. The sixth rotation axis Z6 is angularly shifted, with regard to the fourth rotation axis Z4, around the third rotation axis Z3. Preferably the distance between the first rotation axis Z1 and the fifth rotation axis Z5 is chosen equal to the distance between the first rotation axis Z1 and the second rotation axis Z2. Preferably the distance between the third rotation axis Z3 and the sixth rotation axis Z6 is chosen equal to the distance between the third rotation axis Z3 and the fourth rotation axis Z4.

[0076] Advantageously, the first rotation axis Z1 is materialized by a non-represented first shaft of the first lever 66 which is coaxial and rotationally secured with the output shaft 44b. The stem of the first screwed assembly 78 forms a second shaft of the first lever 66 for the articulation of the rod 76 on the first lever 66 around the second axis Z2. A third shaft 84 fixed with the first lever 66 is used for articulating the third lever 82 on the first lever 66, around the fifth rotation axis Z5.

[0077] On the other hand, the second lever has a first shaft 86 for the articulation of the second lever 68 around the third rotation axis Z3, a second shaft formed by the stem of the second screwed assembly 80 for the articulation of the rod 76 on the second lever 68 around the fourth axis Z4 and a third shaft 88 for the articulation of the third lever 82 around the sixth rotation axis Z6

[0078] The carriage 62 forms a clamping surface S62 configured to cooperate with the abutment surface S50 in order to clamp, between the surfaces S50 and S62, the front-most dropwire 18a, which has been previously brought into its bent separated configuration by the separating knife 36.

[0079] The clamping surface S62 is substantially plane.

[0080] The clamping surface S62 is provided on a portion of the armature 62a which protrudes out of the side bodies 62b and 62c along the longitudinal axis A62, beyond the first guiding support 70, in a direction opposite to the second guiding support 74. The clamping surface S62 is adjacent an extremity 62d of the carriage 62 pointing towards the separating gap G18. The clamping surface S62 is parallel to the longitudinal axis A62.

[0081] The casing 40 is provided with, in other words forms, a guiding surface S40 which is parallel to the transfer direction D12, thus to the longitudinal axis A52 of the groove 52. The guiding surface S40 is perpendicular to the abutment surface S50 and perpendicular to the longitudinal axis A62.

[0082] This guiding surface S40 is located at the same vertical level, along the vertical axis Z, as a contact surface S'62 provided on the first side body 62b. The guiding surface S40 is also located at the same level as a contact surface S'62 provided on the first side body 62b along the first rotation axis Z1. The contact surface S'62 is perpendicular to the longitudinal axis A62 of the carriage 62.

[0083] The first lever 66 carries an actuating cam surface S66, whose surface profile is eccentric relative to the first rotation axis Z1.

[0084] The first lever 66 also carries an ejection-actuating surface S'66, whose surface profile is also eccentric with respect to the first rotation axis Z1 and which is offset, along this first rotation axis, with respect to the obstacle actuating cam surface S66. In other words, the two surfaces S66 and S'66 intersect two different planes parallel to a plane of movement of the articulated structure 64.

[0085] Here, both surfaces S66 and S'66 belong to the first lever 66, thus to the clamping device 60.

[0086] The ejection-actuating surface S'66 is configured to cooperate with an ejection pusher 90 mounted on the casing 40 and rotatable around a seventh rotation axis Z7 parallel to the other rotation axes Z1 to Z6.

[0087] The ejection pusher 90 is provided with a pushing surface S90 and an ejection-driving surface S'90 configured to interact with the ejection-actuating surface S'66 of the first lever 66.

[0088] The ejection pusher 90 also forms a back surface S"90.

[0089] The ejection pusher 90 is movable in rotation around the seventh rotation axis Z7 between an inactive position and an active position. The seventh rotation axis Z7 has a fixed position with respect to the casing 40. In the inactive position of the ejection pusher 90, the back surface S"90 is in abutment against a corresponding abutment surface S"40 of the casing 40 and the ejection pusher 90 does not interact with any dropwire 18 carried by the holding elements 24 of the dropwire transport unit 10. In the active position of the ejection pusher 90, the pushing surface S90 can push a dropwire 18 out of the pins 30 and 32 of the associated holding element 24. When the ejection pusher 90 moves from its inactive position to its active position, its pushing surface S90 moves in the forward direction parallel to longitudinal axis A52 and crosses a plane extending from the abutment surface S50 of the abutment part 50 in retracted position. In particular, when the ejection pusher 90 moves from its inactive position to its active position, its pushing surface S90 crosses the transport path and a vertical plane extending from the front surface 24e of the holding element 24 in a transport ejection position along the transport path. This transport ejection position is located, along the transport path, between the transport transfer position and the transport threading position. The pushing surface S90 goes beyond this vertical plane so that it comes into abutment with a dropwire 18 held by the pins 30 and 32 of the holding element in the transport ejection position.

[0090] The articulated structure 64 is configured to transform a rotational movement of the output shaft 44b of the actuator 44 into a movement of the carriage 62 relative to the casing 40 through different successive positions, namely: a disengaged position represented on figures 1 and 3 to 6; a first intermediate position represented on figures 7 and 8; a second intermediate position represented on figure 9; and a final position represented on figure 10.

[0091] When the carriage 62 is moved between these successive positions, the front-most dropwire 18a is moved along the transfer direction D12 and transferred onto the holding element 24a located in the transport transfer position.

[0092] A rotating movement of the output shaft 44b of the actuator 44 drives the first lever 66 in rotation relative to the casing 40, around the first rotation axis Z1.

[0093] The clamping rotation direction of the first lever 66, when the carriage 62 goes from the disengaged position to the first intermediate position, from the first intermediate position to the second intermediate position and from the second intermediate position to the final position, is represented by arrow R on figures 8, 9 and 10.

[0094] The movement of the first lever 66 driven by the output shaft 44b of the actuator 44 and the corresponding movements of the parts of the articulated structure 64 allows the clamping device 60 starting from the disengaged position to successively reach the first intermediate position, the second intermediate position and the final position mentioned here above.

[0095] In the disengaged position, the clamping device 60 is completely offset from the abutment surface S50 perpendicularly to the transfer direction D12. In other words, the clamping device 60 is completely out of the facing volume V50 facing the abutment surface S50. In other words, the clamping device 60 doesn't face, even partially, the abutment surface S50 along the transfer direction D12. The clamping device 60 is also completely out of the separating gap G18. The clamping spring 81 pushes the clamping carriage 62 along the longitudinal axis A62 in abutment against the first guiding support 70.

[0096] In the disengaged position, the two surfaces S62 and S50 are parallel. In particular, in the disengaged position of the carriage 62, the plane P13 and the plane P24 are not coplanar.

[0097] Due to the deformable parallelogram formed by the articulated structure 64, the clamping surface S62 remains parallel to itself and to the abutment surface S50 during the movement of the carriage 62 from the disengaged position to the first intermediate position.

[0098] In the first intermediate position represented on figures 7 and 8, the clamping surface S62 extends at least partially in the facing volume V50. In the example of the figures, the clamping surface S62 fully crosses the facing volume V50 when the carriage 62 is in the first intermediate position. This clamping surface S62 faces the abutment surface S50 along the transfer direction D12, with the separated front-most dropwire 18a located between these two surfaces S62 and S50. The two surfaces S62 and S50 are parallel and do not clamp the separated front-most dropwire 18a between them yet. The two surfaces S62 and S50 face both sides of this dropwire, respectively the second principal face 18c and the first principal face 18b of the separated front-most dropwire 18a. The abutment part 50 is in advanced position, as in the disengaged position of the carriage 62. The clamping carriage 62 abuts against the casing 40 along a direction parallel to the longitudinal axis A62. In other words, the contact surface S'62 of the carriage 62 lies against the guiding surface S40. This implies that, as from the first intermediate position and when the first lever 66 further rotates in the clamping rotation direction R, the carriage 62 cannot move anymore along a direction parallel to its longitudinal axis A62.

[0099] A further rotation of the first lever 66 in the clamping rotation direction R brings the articulated structure 64 in the configuration of figure 9 where the clamping carriage 62 is in a second intermediate position. In this second intermediate position, the clamping surface S62 extends within the facing volume V50 as in the first intermediate position and cooperates with the abutment surface S50 in the transfer direction D12, with a dropwire in-between, whereas the abutment part 50 is in the advanced position. This allows these two surfaces S50 and S62 starting to clamp the separated front-most dropwire 18a, with the separated front-most dropwire located in-between these two surfaces. Clamping of the dropwire 18a begins since the clamping carriage 62 and the associated clamping surface S62 follow, from the second intermediate position of the carriage 62, a translational path along a direction parallel to the transfer direction D12, due to the cooperation of the two surfaces S'62 and S40. In particular, the clamping surface S62 remains parallel to the abutment surface S50 during the translational displacement of the carriage 62 guided by the cooperation of the surfaces S'62 and S40.

[0100] Further rotation of the first lever 66 in the clamping rotation direction R brings the articulated structure 64 in the configuration of figure 10 where the clamping surface S62 has pushed the dropwire 18a and the abutment part 50 in the backward direction parallel to the transfer direction D12, along the longitudinal axis A52. This movement is guided by the cooperation of the two surfaces S'62 and S40 and results in pushing the abutment part 50 in its retracted position, where its head 50a is in abutment against the stop 56 formed by the casing 40, and engaging the upper portion of the separated dropwire 18a on the two pins 30 and 32 of the holding element 24a located in the transport transfer position.

[0101] The translational movement of the abutment part 50 from its advanced position to its retracted position brings the recess 50c in alignment with the obstacle 58, which is pushed by the spring 59 so that its tip 58a engages into the recess. Thus, the abutment part 50 is automatically locked in its retracted position when it reaches this retracted position under the action of the carriage 62.

[0102] From the disengaged position to the first intermediate position, the carriage 62 follows the movement of the rod 76 relative to the casing 40, i.e. follows the rotation of the second rotation axis Z2 around the first rotation axis Z1. Thus, on a portion of its movement relative to the casing 40 from the disengaged position to the second intermediate position, the carriage 62 follows a circular path CP, with a component of movement parallel to the transfer direction D12 and a simultaneous component of movement parallel to the longitudinal axis A62 and perpendicular to the transfer direction D12.

[0103] This circular path CP is located in a plane parallel to the plane of figures 4 to 6, this plane being transverse to the median plane P16 of the stack 16. Advantageously, this plane is perpendicular to the median plane P16 of the stack 16. Advantageously, this plane is parallel to the transfer direction D12 and parallel to the longitudinal axis A62. This plane is perpendicular to the first rotation axis Z1. This plane is parallel to a plane in which the deformable parallelogram articulated structure 64 is visible. The circular path CP of a point of the clamping surface S62 of the carriage 62 from the disengaged position to the first intermediate position is visible on Figure 8, as a thick axis line. This circular path CP has a radius equal to the distance between the first and second rotation axes Z1 and Z2.

[0104] Between the first intermediate position and the second intermediate position and between the second intermediate position and the final position, the movement of the carriage 62 relative to the casing 40 is restricted by the cooperation between the contact surface S'62 and the guiding surface S40 and follows a linear path. This linear movement is a translation parallel to the transfer direction D12, whereas the rod 76 goes on with a movement having a component of movement parallel to the transfer direction D12 and a simultaneous component of movement perpendicular to the transfer direction D12. The linear path of the carriage 62 is located in the same plane as the circular path CP of the carriage 62, this plane being transverse, in particular perpendicular, to the median plane P16 of the stack 16.

[0105] This is possible due to a sliding movement of the carriage 62 along the longitudinal axis A62, with respect to the two guiding supports 70 and 74 and with respect to the rod 76, as shown by the respective positions of parts 62, 70 and 74 on figures 4, 8, 9 and 10.

[0106] The translation of the carriage 62 along the longitudinal axis A62 with respect to parts 70, 74 and 76 occurs against the action of the clamping spring 81, which pushes back the carriage 62 toward its position represented on figures 1 and 3 to 6, with respect to parts 70, 74 and 76. On the other hand, along the transfer direction D12, the clamping surface S62 is accurately connected to the first lever 66, due to the cooperation of the carriage 62 with the guiding surfaces 70a, 70b, 74a, 74b. This allows a precise control of position of the clamping surface S62 and the application of a precisely controlled effort along the transfer direction D12, sufficient to move the separated front-most dropwire 18a into the transport transfer position and the abutment part 50 into the retracted position of figure 10.

[0107] During the rotation of the first lever 66 in the clamping rotation direction R to bring the carriage 62 from the disengaged position to the final position, the planes P13 and P24 become closer. In the final position of figure 10, a plane P56 including the fifth and sixth rotation axis Z5 and Z6 is out of the volume delimited between the plane P13 and the plane P24. In all configurations of the articulated structure 64, the plane P56 is parallel to the plane P13. The third lever 82 has the function of avoiding jamming of the deformable parallelogram formed by the articulated structure 64 in case the first, second, third and fourth rotation axes Z1, Z2, Z3 and Z4 are all approximately aligned.

[0108] The movement of the abutment part 50 between the advanced position and the retracted position is induced only by the rotation of the lever 66 driven the actuator 44 and the movement of the carriage 62 between the second intermediate position and the final position.

[0109] In the final position of figure 10, when the actuator 44 is powered by the controller 46 to further rotate the first lever 66 in the direction of arrow R on figure 10, the force needed to further move the clamping surface S62 in the transfer direction D12, along the longitudinal axis A52, significantly increases because the head 50a is already in contact with the stop 56 of the casing 40. This increase in the force applied by the actuator 44 is detected by the controller 46, which stops the rotation of the output shaft 44b, thus the rotation of the first lever 66, in the clamping rotation direction represented by the arrow R.

[0110] A sensor 96, such as a rotary encoder, is used to detect a final angular position of the output shaft 44b and / or of the first lever 66 around the first rotation axis Z1, when the actuator is stopped by the controller 46, when the carriage 62 is in the final position. The final angular position detected by the sensor is compared to a reference position, which has been previously determined, before starting the drawing-in process. This reference position is the angular position of the output shaft 44b and / or of the first lever 66 around the first rotation axis Z1, when the clamping surface S62 is in contact with the abutment surface S50 in retracted position and when no dropwire is present between these two surfaces.

[0111] In a variant, the reference position is the angular position of the output shaft 44b and / or of the first lever 66 around the first rotation axis Z1, when the clamping surface S62 is in contact with the abutment surface S50 in retracted position and when only a single correct dropwire is present between these two surfaces. The thickness value of the dropwires 18 within the stack 16 or a predetermined acceptable range for this thickness value has been given to the controller 46 before starting the drawing-in process.

[0112] The controller 46 is configured to determine an information relating to the thickness of the separated front-most dropwire 18a clamped between the clamping surface S62 in the final position and the abutment surface S50 in the retracted position of figure 10, based on a comparison between the final position of the carriage 62 sensed by the sensor and the reference position.

[0113] For example, the information relating to the thickness is the measured value of the thickness of the separated front-most dropwire 18a clamped between the clamping surface S62 in the final position and the abutment surface S50.

[0114] If the measured thickness value of the dropwire 18a clamped between the surfaces S62 and S50 in the final position of figure 10 is within a predetermined acceptable range, the dropwire transport unit 10 moves the holding element 24 carrying this dropwire towards the transport threading position and, from there, towards one of the discharged positions.

[0115] If the measured thickness value determined by the controller 46 is out of the predetermined acceptable range, this might be because the dropwire is defective, for instance because it is partly plastically folded and damaged, or this might be because a double dropwire, i.e. two dropwires that stick to each other, has been bent at the same time by the separating knife 36 by mistake and clamped between the two surfaces S62 and S50.

[0116] In such a case, as explained here below, the ejection pusher 90 is used to free the holding element 24a which was previously in the transport transfer position from any dropwire 18.

[0117] A separation and transfer process of a given front-most dropwire 18a of the stack 16 of dropwires 18 occurs as follows: At the beginning of this separation and transfer process, the carriage 62 is in the disengaged position and, as the clamping device 60 is completely offset from the abutment surface S50 perpendicularly to the transfer direction D12, the clamping device 60 is completely out of the bending path of the next front-most dropwire 18a to be separated, i.e. out of the separating gap G18. A free holding element 24a, that is a holding element which does not carry a dropwire 18, is placed at the transport transfer position by the dropwire transport unit 10 with its front face 24e facing the first principal face 18b of the front-most dropwire 18a of the stack 16. The movable pin 30 of the holding element 24a is depressed by release means 94 represented respectively in active position and in inactive position in figures 10 and 11. The abutment part 50 lies against stop 55 and the obstacle 58 is in its second position. The abutment surface S50 faces the first principal face 18b of the front-most dropwire 18a of the stack 16.

[0118] This is the configuration of the dropwire transfer module 12 represented on figures 1 and 3 to 6, where the carriage 62 is in the disengaged position and completely offset from the abutment surface S50 perpendicularly to the transfer direction D12.

[0119] When the separated dropwire 18a is deformed by bending, via the separating knife 36, the support rail 14 still extends through the upper opening 19 of the front-most dropwire 18a and the fixed pin 32 of the holding element 24a in the transport transfer position is engaged in the upper opening 19 of the front-most dropwire 18a. This front-most dropwire 18a is in contact with the abutment surface S50 or close to this abutment surface and the separating gap G18 is created between the front-most dropwire 18a and the rest of the stack 16. The abutment surface S50 is in the advanced position. The bottom end of the front-most dropwire 18a abuts against the lower support member 38.

[0120] Then, the actuator 44 of the dropwire transfer module 12 is actuated by the controller 46 and rotates its output shaft 44b in the clamping rotation direction R around the first rotation axis Z1. The articulated structure 64 of the clamping device 60 is progressively deformed due to the rotation of the first lever 66 around the first rotation axis Z1. This progressive deformation of the articulated structure 64 moves the carriage 62, along the circular path CP centered on an axis parallel to the first rotation axis Z1, into the first intermediate position where the clamping surface S62 is engaged into the separating gap G18, between the bent front-most separated dropwire 18a and the stack 16, and penetrates into the facing volume V50. In this first intermediate position of the carriage 62, the clamping surface S62 is close to the second principal face 18c of the bent front-most separated dropwire 18a and, faces, the abutment surface S50 of the abutment part 50 along the transfer direction D12 with the front-most dropwire 18a in-between. The abutment part 50 is still in advanced position, under the action of the spring 54.

[0121] When the actuator 44 continues rotating its output shaft 44b in the clamping rotation direction R, a further deformation of the articulated structure 64 induces that the rod 76 goes on moving along a circular path and that the carriage 62 slides along the guiding surface S40 of the casing 40. This moves the clamping surface S62 parallel to the guiding surface S40, thus parallel to the transfer direction D12, into contact with the second principal face 18c of the bent front-most separated dropwire 18a and clamps the front-most dropwire 18a between the clamping surface S62 and the abutment surface S50. The dropwire transfer module 12 is then in the configuration of figure 9, where the carriage 62 is in the second intermediate position.

[0122] When the rotation of the output shaft 44b and the first lever 66 continues in the clamping rotation direction R, further movement of the clamping surface S62 occurs in translation, parallel to the transfer direction D12, which brings the front-most dropwire 18a towards the front face 24e of the holding element 24a present in the transport transfer position. This further engages the fixed pin 32 in the dropwire upper opening 19 and retracts the abutment part 50 against the action of the spring 54, until the head 50a abuts the fixed stop 56 formed by the casing 40, when the abutment part 50 reaches its retracted position. This brings the first principal face 18b of the separated front-most dropwire 18a in abutment against the front face 24e of the holding element 24a located in the transport transfer position and the upper pin 30 engages the upper opening of the separated front-most dropwire 18a. The dropwire transfer module 12 is then in the configuration of figure 10, where the carriage 62 is in the final position.

[0123] In this final position of the carriage 62, the obstacle actuating cam surface S66 is out of engagement with the obstacle 58, which, under the action of the spring 59, engages its tip 58a into the recess 50c, as soon as the tip 58a faces the recess 50c. The actuating cam surface S66 is not operational in this final position of the carriage 62. In other words, the obstacle actuating cam surface S66 can move the obstacle 58 from its first position to its second position when the carriage 62 is in a position distant from the final position.

[0124] In this final position, an increase of the force necessary to further move the clamping surface S62 is detected by the controller 46 and the actuator 44 is stopped, as explained here above. In this final position of the carriage 62, the value of the thickness of the dropwire(s) clamped between the surfaces S62 and S50 is determined by comparison of the final position sensed by the sensor with the reference position mentioned here above. In this final position, the separating knife 36 is released by the dropwire separation device 8.

[0125] Then, the actuator 44 is piloted to rotate its output shaft 44b in a direction around the first rotation axis Z1 opposite to the clamping rotation direction R, that is in an unclamping rotation direction represented by arrow R' on figure 11. The clamping device 60 reaches a third intermediate position located between the second intermediate position of figure 9 and the final position of figure 10, in which the clamping surface S62 has slightly moved toward the second intermediate position, that is away from the abutment surface S50, whereas the abutment part 50 stays in its retracted position since it is blocked in this position by the obstacle 58, aside from the operating clearances between the tip 58a and the recess 50c . The clamping action of the front-most dropwire 18a by the clamping device 60 is released and the release means 94 release the movable pin 30, so that the dropwire 18a can slide between the clamping surface S62 and the abutment surface S50, these two surfaces guiding the movement of the dropwire 18a in order to guarantee that the dropwire does not escape out of the holding element 24a in the transport transfer position. In other words, the separated front-most dropwire 18a reaches its transport configuration and elastically deforms to recover a substantially vertical configuration, in which it cooperates with the two holding pins 30 and 32, as shown in figure 11.

[0126] Advantageously, the fixed pin 32 cooperates with the bottom of the upper opening 19 of the front-most dropwire 18a and the movable pin 30 cooperates with the top of this upper opening 19, so that this dropwire 18a is in holding configuration and firmly held by the holding element 24a. In the configuration represented on figure 11, the support rail 14 is no more engaged with the front-most dropwire 18a. This dropwire 18a now extends in a plane globally parallel to the front surface 24e of the holding element 24a, which is substantially a vertical plane.

[0127] The clamping device 60 is further moved with the first lever 66 in the unclamping rotation direction R', in rotation around the first rotation axis Z1. When the actuating cam surface S66 of the first lever 66 reaches the obstacle, it pushes the obstacle 58 out of the recess 50c which frees the abutment part 50. Then, the spring 54 pushes the abutment part 50 back in its advanced position and in abutment against the stop 55. In particular, the actuating cam surface S66 can move the obstacle 58 from its first position to its second position only when the carriage 62 is out of the path extending from the final position to the third intermediate position.

[0128] Even if the actuating cam surface S66 stops its cooperation with the obstacle 58 at this stage, the obstacle 58 stays in its second position because it slides on the outer peripheral surface of the stem 50b, out of the recess 50c.

[0129] The rotation of the clamping device 60 in the unclamping rotation direction R' brings the carriage 62 back into the disengaged position.

[0130] If, with the thickness information determined by the controller 46, the controller 46 assumes that only one dropwire 18 has been separated and that the thickness of this dropwire corresponds to the thickness of the dropwire to be drawn-in. Then, the dropwire is transported into the transport threading position without any stop at the transport ejection position.

[0131] A new free holding element 24 is brought into the transport transfer position to receive the next separated dropwire 18a. The dropwire transfer module 12, with the carriage 62 in disengaged position, is then ready for transferring another dropwire, from the stack 16 to the dropwire transport unit 10.

[0132] On the other hand, if with the thickness information determined by the controller, the controller 46 assumes that the clamped dropwire is defective, for instance because a double dropwire or a damaged dropwire has been separated by the separating knife 36, the holding element 24a coming out of the transport transfer position is stopped in the transport ejection position with the dropwire hanging down from the two pins 30 and 32 and with the first principal face 18b facing the pushing surface S90 of the ejection pusher 90,.

[0133] If the holding element 24 is stopped in the transport ejection position, the actuator 44 is piloted by the controller to further rotate the first lever 66 in the unclamping rotation direction R', beyond the disengaged position represented on figure 11, up to reaching the position of figure 12 where the ejection-actuating surface S'66 of the first lever 66 contacts and pushes the ejection-driving surface S'90 of the ejection pusher 90. This induces an ejection rotational movement of the ejection pusher 90 around the seventh rotation axis Z7, in the direction of arrow R" on figure 12.

[0134] Advantageously, the direction of rotation R" of the ejection pusher 90 around the seventh rotation axis Z7 is oriented in the same direction as the unclamping rotation direction R' of the first lever 66 around the first rotation axis Z1.

[0135] The ejection rotational movement R" induces that the pushing surface S90 of the ejection pusher 90 pushes the defective dropwire(s) 18, hanging down from the holding element 24 located vertically above the pushing surface S90, out of engagement with the two pins 30 and 32, as shown in figure 12.

[0136] The defective dropwire(s) 18 is / are then evacuated by gravity.

[0137] At the end of the ejection sequence represented in figure 12, the actuator 44 is driven in the clamping rotation direction R, , which brings the first lever 66 in a position where its ejection-actuating surface S'66 is moved away from the ejection-driving surface S'90 of the ejection pusher 90. The ejection pusher is pulled back into its inactive position by a spring 92, here a tension spring interposed between the casing 40 and the ejection pusher 90, with its back surface S"90 in contact with the abutment surface S"40 of the casing 40.

[0138] Then, the holding element 24, which has been freed from the defective dropwire(s), is brought back to the transport transfer position by one of the two belts 20 and 22, in a reverse movement along the transport path. The separation and transfer process starts again.

[0139] According to a non-represented variant of the invention, no deformable parallelogram structure is used and the carriage 62, or the rod 76 supporting the carriage 62, is secured, in rotation around the first rotation axis Z1, with the first lever 66. For example, another deformable quadrilateral structure can be used. In such a case, the orientation of the clamping surface S62 is not always parallel to the abutment surface S50. This orientation can be adjusted, e.g. with a spring, in order to adapt the contact of the clamping surface S62 with the abutment surface S50, when the separated front-most dropwire 18a is clamped in-between these two surfaces.

[0140] According to another non-represented variant of the invention, instead of moving within a plane that is transverse to the median longitudinal plane P16 of the dropwire stack 16, the carriage 62 can be moved by the articulated structure 64 in a direction or direction(s) parallel this median longitudinal plane. In such a case, the movement of the carriage 62, and in particular the circular path of the carriage 62, lies in a substantially vertical plane and the clamping surface S62 can reach the abutment surface S50 from above. In such a case, the first rotation axis Z1 is substantially horizontal, thus transverse to the transfer direction, and, in the separated configuration of the front-most dropwire 18a by an adapted dropwire separation device, the separating gap G18 is open parallel to the direction of the vertical axis Z to enable the clamping surface S62 to be introduced into the separating gap.

[0141] According to another non-represented variant of the invention, instead of realizing the dropwire separation with a separating knife 36, which bends the front-most dropwire to be separated, a separating knife can be introduced between the front-most dropwire 18a and the stack 16, in order to incline the front-most dropwire to be separated from the stack, without bending this front-most dropwire. This approach also results in creating a separating gap between the separated front-most dropwire 18a and the stack 16.

[0142] According to another non-represented variant of the invention, a linear actuator can be used instead of the rotative actuator 44 of the invention. A movement transmission system, such as a rack and pinion mechanism, can be used to transform the translational output movement of the linear actuator into a rotation movement of the first lever 66 around the first rotation axis Z1. The actuation part of the linear actuator is guided, in its translation relative to the casing, by the casing itself.

[0143] According to another non-represented variant of the invention, actuating surfaces comparable to surfaces S66 and / or S'66 are provided on the second lever 68, which also belongs to the clamping device 60. In such a case, the second lever 68 is preferably closer to the abutment part 50 than the first lever 66, in particular along longitudinal axis A62.

[0144] According to another non-represented variant of the invention, the dropwire feeding unit 6 includes several stacks of dropwires and several supporting rails for these stacks.

[0145] The above mentioned embodiments and variants of the invention can be combined within the scope of the invention defined by the appended claims.

[0146] The invention described here above induces many advantages, including the ones mentioned here above and the following advantages: movements of the clamping device 60 driven by the rotating part 44b of the actuator 44 are fast and precisely controlled, which allows quickly and accurately loading a separated front-most dropwire 18a on a holding element 24a located in the transport transfer position; the fixed part 44a of the actuator 44 is stationary with respect to the casing 40, which is simpler to implement than a case where an actuator must be moved with respect to a casing, as in the prior art; transfer of the separated front-most dropwire 18a from the disengaged position represented on figures 3 to 6, to the final position represented on figure 10 is obtained by cooperating with this dropwire 18a via its two principal faces 18b and 18c, for clamping and for guiding the dropwire between the second intermediate position and the final position. This limits the risks of damaging the dropwire and ensures a good positioning of the dropwire on the holding element 24a located in the transport transfer position; the movement of the carriage 62, from the disengaged position to the first intermediate position is a circular movement with components in the transfer direction D12 and in a direction perpendicular to the transfer direction, in particular a direction parallel to the longitudinal axis A62. This allows the clamping surface S62 quickly reaching the first intermediate position, which is advantageous in terms of speed of the process. Moreover, this movement is driven by a single actuator 44, which is simple and reliable; the articulated structure 64 of the clamping device forms a deformable parallelogram, so that the clamping surface S62 keeps the same orientation with respect to the transfer direction D12. In particular, the clamping surface S62 is always parallel to the abutment surface S50; the deformable parallelogram formed by the articulated structure 64 enables a combined movement in the transfer direction D12 and in a transverse direction perpendicular to the transfer direction D12, within a small longitudinal space, along the transfer direction D12. This enables the dropwire transport unit 10 to be closer to the dropwire feeding unit 6 along the transfer direction D12; no additional actuator is required to move the abutment part 50 from the advanced position into the retracted position since this movement occurs as a result of the displacement of the clamping surface S62; the cooperation between the guiding surface S40 of the casing 40 and the contact surface S'62 of the carriage 62 restricts the movements of the clamping surface S62, from the first intermediate position to the final position, to a translational movement along the transfer direction D12. This reduces the transverse effort on the separated front-most dropwire 18a located between the two surfaces S62 and S50. As the transfer direction D12 is parallel to the thickness of the separated front-most dropwire 18a, the position of the clamping surface S62 along the direction perpendicular to the transfer direction D12, i.e. along the longitudinal axis A62, does not depend on the thickness of the dropwire. Thus, the position of the clamping carriage 62 reached in the final direction is directly dependent on the thickness of the dropwire. This position, thus this thickness, can be accurately determined by the controller 46, which facilitates evacuation of a defective or double dropwire. the thickness of the separated dropwire(s) is measured in the final position of the carriage, when the dropwire is already engaged on the holding element 24a present in the transport transfer position, which enables a quick ejection process, with the ejection pusher 90, if the thickness is not correct; the first rotating lever 66 and / or the second rotating lever 68 carry actuating surfaces S66, S'66... that cooperate with the obstacle 58 and / or the ejection pusher 90 in predetermined angular orientation ranges of these levers relative to the casing, around the first and third rotation axes Z1 and Z3. No additional actuator is necessary to activate the obstacle 58 nor the ejection pusher 90, which keeps the number of actuators low, in particular equal to one; the abutment surface S50 and the clamping surface S62 are offset vertically with respect to the holding element 24a present in the transport transfer position, so that clamping of the separated front-most dropwire 18a occurs out of the vertical level of the holding element. This allows engaging this dropwire with the two holding pins 30 and 32 of the holding element 24a by using the elasticity of the dropwire between the position of figure 9 and the position of figure 10; when the abutment part 50 is in its retracted position, the abutment surface S50 extends in the same vertical plane as, or preferably in front of, the external front surface 24e of the holding element 24a in the transport transfer position, from which the two pins 30 and 32 protrude to the front. This allows the separated front-most dropwire 18a to freely engage the two holding pins due to its elasticity, when the clamping device 60 moves from the position of figure 9 to the position of figure 10.

Claims

1. A dropwire transfer module (12) for a drawing-in machine (2), said dropwire transfer module including - a casing (40); - an abutment part (50) movable relative to the casing, parallel to a transfer direction (D12), between an advanced position and a retracted position, said abutment part forming an abutment surface (S50); - an actuator (44) including a housing (44a) fixed with the casing (40) and an actuation part (44b) movable with respect to the housing; - a clamping device (60) including a first lever (66) and a carriage (62) forming a clamping surface (S62), the clamping surface (S62) and the abutment surface (S50) being configured to clamp a dropwire (18a) in-between, characterized in that - the first lever (66) is configured to be reciprocally rotated relative to the casing (40) by the actuation part (44b) of the actuator around a first rotation axis (Z1), - the first rotation axis (Z1) has a fixed position with respect to the casing (40) and is transverse to the transfer direction (D12); - the first lever (66) is connected to the carriage (62) in such a way that a rotational movement of the first lever (66) relative to the casing (40) around the first rotation axis (Z1) in a clamping rotation direction (R) causes a movement of the carriage (62) relative to the casing (40) into at least the following successive positions ∘ a disengaged position, where the clamping device (60) is completely offset of the abutment surface (S50) perpendicularly to the transfer direction (D12); ∘ an intermediate position, where the clamping surface (S62) cooperates with the abutment surface (S50) in the transfer direction (D12), with a dropwire (18a) in-between, the abutment part (50) being in the advanced position ; ∘ a final position, where the clamping surface (S62) and the abutment surface (S50) clamp the dropwire (18a) between them, the abutment part (50) being in the retracted position; - at least on a portion of the movement of the carriage (62) between the disengaged position and the intermediate position, the carriage (62) follows a circular path (CP), which is located in a plane perpendicular to the first rotation axis (Z1).

2. The dropwire transfer module of claim 1, wherein the clamping device includes a rod (76) articulated on the first lever (66) around a second rotation axis (Z2) and wherein the rod (76) supports the carriage (62).

3. The dropwire transfer module of claim 2, wherein - the clamping device (60) includes a second lever (68) rotatable relative to the casing (40) around a third rotation axis (Z3) having a fixed position with respect to the casing (40); - the rod (76) is articulated on the second lever (68) around a fourth rotation axis (Z4); - the clamping surface (S62) is parallel to the abutment surface (S50); - the first, second, third and fourth rotation axes (Z1, Z2, Z3, Z4) are parallel; and - the casing (40), the first lever (66), the second lever (68) and the rod (76) form a deformable parallelogram structure having the first, second, third and fourth rotation axes (Z1, Z2, Z3, Z4) as articulated corners.

4. The dropwire transfer module of claim 3, wherein a third lever (82) is articulated - on the first lever (66), around a fifth rotation axis (Z5), angularly shifted, with respect to the second rotation axis (Z2), around the first rotation axis (Z1), and - on the second lever (68), around a sixth rotation axis (Z6), angularly shifted, with respect to the fourth rotation axis (Z4), around the third rotation axis (Z3); the fifth rotation axis (Z5) and the sixth rotation axis (Z6) being parallel to the first rotation axis (Z1).

5. The dropwire transfer module of any one of claims 2 to 4, wherein - the carriage (62) is supported on the rod (76) with only a possibility of relative translation along a direction perpendicular to the second rotation axis (Z2); - the casing (40) forms a guiding surface (S40) parallel to the transfer direction (D12); and - the carriage (62) comprises a contact surface (S'62) configured to come into cooperation with the guiding surface (S40) when the first lever (66) rotates around the first rotation axis (Z1) in the clamping rotation direction (R) for guiding the carriage (62) in translation along the transfer direction (D12), between the intermediate position and the final position.

6. The dropwire transfer module of any preceding claim, wherein - an elastic member (54) interposed between the casing (40) and the abutment part (50) biases the abutment part in a forward direction parallel to the transfer direction (D12), toward the advanced position; and - in the retracted position, the abutment part (50) abuts, in a backward direction, against a stop (56) formed by the casing.

7. The dropwire transfer module of any preceding claim, wherein the actuation part (44b) of the actuator (44) is an output shaft rotatable around the first rotation axis (Z1) and wherein the first lever (66) is fast in rotation, around the first rotation axis (Z1), with the output shaft.

8. The dropwire transfer module of claim 7, wherein an angular position of the output shaft around the first rotation axis (Z1), when the carriage (62) is in the final position, is monitored by a sensor (96) and wherein a controller (46) is configured to determine an information relating to the thickness of a dropwire located between the abutment surface (S50) and the clamping surface (S62) in the final position, based on a difference between the angular position monitored by the sensor and a reference position.

9. The dropwire transfer module of any preceding claim, wherein the dropwire transfer module (12) further comprises an obstacle (58) mounted on the casing (40) with a possibility of movement relative to the abutment part (50) between - a first position, where the obstacle (58) cooperates with the abutment part (50) in the retracted position and opposes a movement of the abutment part toward the advanced position; and - a second position, where the obstacle (58) does not oppose the movement of the abutment part (50) from the retracted position to the advanced position, 10. The dropwire transfer module of claim 9, wherein - an elastic member (59) biases the obstacle (58) toward its first position; - the clamping device (60) comprises an actuating cam surface (S66) moved by the actuation part (44b) of the actuator (44) and configured for moving the obstacle from its first position to its second position, when the carriage (62) is in a position distant from the final position.

11. A drawing-in machine (2) comprising - a frame (4); - a dropwire feeding unit (6) supporting at least one stack (16) of dropwires (18); - a dropwire separation device (8) configured to separate a front-most dropwire (18a) from the stack (16) by putting it into a separated configuration, where a separating gap (G18) is formed between the front-most dropwire (18a) and the next dropwire (18) of the stack; - a dropwire transport unit (10) with at least one holding element (24) moved relative to the frame (4) of the drawing-in machine (2) along a transport path, which goes from a transport transfer position, where the separated dropwire (18a) is brought on the holding element, to one of several discharge positions, where the dropwire is discharged from the holding element onto a receiving device (28), via a transport threading position, where a warp yarn is inserted through the dropwire; - a dropwire transfer module (12) according to one of claims 1 to 10 for transferring a dropwire (18a), from the separated configuration onto a holding element (24a) in the transport transfer position; wherein the casing (40) of the dropwire transfer module is fixed with regard to the frame (4) of the drawing-in machine.

12. The drawing-in machine of claim 11, wherein the abutment surface (S50) of the abutment part (50) and the clamping surface (S62) of the carriage (62) of the dropwire transfer module (12), in the final position of the carriage (62), are vertically offset from a holding element (24a) located in the transport transfer position.

13. The drawing-in machine of one of claims 11 and 12, wherein the plane, in which the circular path (CP) of the carriage (62) moving between the disengaged position and the intermediate position is located, is a plane transverse to a median longitudinal plane (P16) of the stack (16), preferably a plane parallel to the transfer direction (D12).

14. The drawing-in machine of one of claims 11 to 13, wherein the dropwire transfer module (12) further comprises an ejection pusher (90) movable with respect to the casing (40) between - an inactive position, where the ejection pusher (90) does not interact with any dropwire (18) carried by the dropwire transport unit (10), and - an active position, where the ejection pusher (90) pushes a dropwire away from a holding element (24), wherein, the clamping device (60) comprises an ejection surface (S'66), moved by the actuation part (44b) of the actuator (44) and configured to come into cooperation with an ejection driving surface (S'90) of the ejection pusher (90), to move the ejection pusher from its inactive position to its active position, when the first lever (66) rotates with regard to the casing (40) around the first rotation axis (Z1) in an unclamping rotation direction (R') opposite to the clamping rotation direction (R).

15. The drawing-in machine of one of claims 11 to 14, wherein the dropwire separation device (8) comprises a separating knife (36) configured to bend the front-most dropwire (18a) of the stack (16) when the front-most dropwire (18a) is in its separated configuration, wherein the dropwire feeding unit (6) and the dropwire transport unit (10) are located relative to one another such that, in its separated configuration, the separated front-most dropwire (18a) is partially in engagement with a pin (32) of the holding element (24a) in the transport transfer position.

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