Outdrive lever with follower rollers of a cam-operated armor mechanism and its manufacturing process

Abstract

The roller follower exit lever of a cam-operated armor mechanism and its manufacturing method. The present invention relates to a roller follower exit lever of a cam-operated armor mechanism comprising a flat body (24), two inner flanges (30A), two outer flanges (32A), two rollers (22A), and at least two rivets (40) for attaching at least one of the outer flanges (32A) to the flat body (24). The rivets (40) pass through the body (24) and one outer flange (32A). Each rivet (40) comprises a rivet body (42), of revolution about a rivet axis (X40) and extending between a rivet head (44) and a rivet foot (46), and at least one first groove (48) formed on an external peripheral surface (S40), in which a portion of a flange (30A, 32A) forms a ridge (52). The flange (30A, 32A) comprises, on its external face, an impression (50) for the recess of the portion of the flange that forms the ridge (52).The indentation (50) is centered on the rivet axis (X40). Figure for the abbreviation: figure 4.

Description

Title of the invention: Output lever with follower rollers for a cam-type armor mechanism and its manufacturing method

[0001] The present invention relates to a roller follower output lever used in a cam armour mechanism and to a method of manufacturing such a lever.

[0002] In the field of weaving looms, cam-operated weave mechanisms are known which comprise a series of oscillating levers in number equal to that of the heddle frames of the loom. Each oscillating lever is designed to be coupled to one of the heddle frames and is equipped with two rollers which cooperate with the two tracks of a complementary cam driven in rotation by a common shaft. The two tracks of the same cam are axially offset and the rollers carried by the associated output lever must have the same axial offset as the tracks of the cam.

[0003] During operation, only one of the rollers of the output lever is stressed at any given time. Due to the axial offset of the stressed roller, the output lever is subjected to significant mechanical stresses, which can lead to deformation of certain elements of the lever, in particular the elements receiving the rollers.

[0004] To limit these deformations, it is known, for example from CN203807652U, to mount the rollers between a flange machined in the thickness of the lever body and an attached flange, fixed to the lever body by means of a deformable rivet.

[0005] Furthermore, it is known from WO2002 / 098106A1 that the rollers can be mounted between two flanges attached to the lever body, one of the flanges being placed in a hollow housing in a lateral surface of the lever body. The attached flanges are fixed by means of deformable rivets.

[0006] The assembly of the flanges on the lever body requires a step of pre-drilling the levers and the flanges in order to be able to insert the deformable rivets. This pre-drilling step and the use of deformable rivets create a clearance which is unfavorable to the assembly of the flanges on the lever body, to the precision of the positioning of the rollers, which weakens the connection between the flanges and the lever body and which disrupts the drive kinematics of the levers.

[0007] It is these drawbacks that the invention more particularly intends to remedy by proposing a new lever with follower rollers which allows a rigid and play-free assembly of the flanges on the lever body.

[0008] To this end, the invention relates to an output lever with follower rollers for a cam-type armor mechanism comprising a flat body intended to support an articulation with a connecting rod for transmitting the oscillating movement of the output lever to a smooth frame and comprising a first face and a second face opposite and defining between them a median plane and a bore centered on a main axis intended to receive a bearing or a bushing mounted on a shaft of the levers of the cam armor mechanism, a first internal flange in one piece with the body or attached to the second face of the body, a second internal flange in one piece with the body or attached to the second face of the body, a first external flange, attached to the first face of the lever body, opposite the first internal flange, a second external flange, attached to the second face of the lever body, opposite the second internal flange, a first roller intended to follow a first track of a cam of the armor mechanism and taken in a yoke in a first space provided between the first external flange and the first internal flange,a second roller intended to follow a second track of the cam of the armor mechanism and held in a yoke in a second space provided between the second outer flange and the second inner flange and at least two rivets for fixing at least one of the outer flanges to the flat body, the rivets passing through the lever body and the outer flange. According to the invention, each rivet comprises a rivet body in the form of a solid of revolution around a rivet axis extending between a rivet head flush with an external face of a first element among the outer flange and the inner flange, a rivet foot flush with an external face of the second element among the outer flange and the inner flange, at least one first rivet groove provided on an external peripheral surface of the rivet in which a portion of the first or second element forms a bead of a shape complementary to the first groove,the first and / or the second element comprises, on its external face, a depression imprint of the portion of the first or second element which forms the bead and the depression imprint is centered on the rivet axis.

[0009] Thanks to the invention, the rivets provided with a groove and the depressions of the elements assembled among the inner flange and the outer flange, allow precise assembly of the outer flanges to the inner flanges of the lever. Also thanks to the invention, an assembly method using rivets provided with a groove and the driving in of the portion of the first or second element makes it possible to secure the outer flanges and the inner flanges. The driving in impression makes it possible to have, within the first or second element, enough material to constitute the portion engaged in the groove of a rivet. The element in which the rivet is inserted perfectly matches the shape of the rivet and the cooperation between the peripheral groove of the rivet and the portion of the first or second element received in this groove ensures effective anchoring of the rivet in this element. The use of rivets with groove and beads formed by a portion of material corresponding to a depression imprint makes it possible to obtain a roller lever followers with good mechanical strength and which ensure optimal operation of the cam armor mechanism.

[0010] According to other advantageous aspects of the invention, the output lever with follower rollers comprises one or more of the following characteristics, taken individually or in all technically possible combinations: - The rivet head has a maximum diameter strictly greater than the diameter of the rivet body and in that the first groove is formed around the rivet foot. - The rivet head comprises a frustoconical side wall converging towards the rivet foot, and an angle at the top of the frustoconical side wall is less than 90°, preferably less than 60°, preferably less than 40°. - A second groove is provided on the external peripheral surface of the rivet, around the rivet body near the rivet head, the first groove is provided on the external peripheral surface of the rivet, around the rivet foot, the first groove receives a bead from the second element, of a shape complementary to the first groove, and the second groove receives a bead from the first element, of a shape complementary to the second groove. - The depth of the first groove or at least one of the grooves is greater than 0.2 millimeters, preferably greater than 0.4 millimeters, more preferably greater than 0.5 millimeters. - The driving imprint is annular, it has an internal diameter equal to the diameter of the rivet body and a bottom of the imprint is arranged, along the rivet axis, between the first groove of the perforating rivet and the external face of the first and / or second element which comprises the driving imprint. - A ratio between the radius of the circumscribed circle of the driving imprint and the radius of the perforating rivet is greater than 1.25, preferably greater than 1.5, more preferably greater than 2. - The depth of the driving impression, measured along the rivet axis, is greater than 0.5 millimeters, preferably greater than 0.8 millimeters, more preferably greater than 1 millimeter. - The external face of the first and / or second element which comprises the driving imprint extends in a semi-circular zone centered on the rivet axis with a circle radius preferably greater than or equal to 1.5 times the radius of the rivet, preferably greater than or equal to 2 times the radius of the rivet and more preferably greater than or equal to 3 times the radius of the rivet. - A reference plane intersecting with the first groove is arranged at a distance from the external face of the first or second element, measured along the axis of rivet, less than 3 millimeters, preferably less than 2 millimeters, more preferably less than 1 millimeter. - The rivet foot comprises an end face perpendicular to the rivet axis and a cylindrical joining edge between the end face and the external peripheral surface of the rivet forms a right angle. - The diameter of the rivet is greater than the cumulative thickness, measured along the rivet axis, of the flat body of the lever and an external flange. - The outer flange includes a tab that extends along a lubrication axis and is configured to guide lubricant from a roller to the bore of the lever body. - The outer peripheral surface of the rivet body comprises a first outer peripheral surface portion received in the first member and a second outer peripheral surface portion received in the second member, and the first outer peripheral surface portion and the second outer peripheral surface portion are concentric and of the same diameter. - Each rivet is a perforating rivet. The use of perforating rivets makes it possible to secure the outer flanges to the inner flanges without the need to pre-drill the elements before assembly. The element in which the perforating rivet is inserted perfectly matches the outer peripheral surface of the perforating rivet body, which limits radial clearances around the perforating rivet body, limits degradation of the radial cooperation surfaces, and contributes to effective anchoring of the perforating rivet in this element. For the purposes of the invention, a perforating rivet is a rivet which is capable of perforating the elements in which it is positioned without being significantly deformed.

[0011] The invention also relates to a method of manufacturing an output lever as described above comprising in accordance with the invention at least the following steps: a. driving the rivet until the rivet foot is flush with the external face of the second element, the rivet being pushed by an external press tool configured to exert a pushing force on the rivet along the rivet axis (X40); and b. pushing back a portion of the second element to form a bead of complementary shape to the throat of the perforating rivet by means of an external die centered on the rivet axis and marking a depression imprint around the rivet foot on the external face of the second element and / or a portion of the first element to form a bead of complementary shape to the throat of the perforating rivet by means of an external die centered on the rivet axis and marking a recess imprint around the rivet head on the external face of the first element.

[0012] According to other advantageous aspects of the invention, the method of manufacturing an output lever comprises one or more of the following characteristics, taken individually or in all technically possible combinations: - The manufacturing process includes at least the following preliminary steps: a. cut, using a rivet which is a perforating rivet, the first element in its thickness, b. cutting, using the perforating rivet, the second element in its thickness, the perforating rivet being pushed using the external press tool along the rivet axis. - The manufacturing method comprises an additional step of positioning the second element on the first element at an overlap zone in the external press tooling after step c) and before step d). - The manufacturing method comprises cutting, driving and pushing steps similar to steps a) to d) for a second rivet, which is a perforating rivet positioned at a distance from the first rivet. - The manufacturing method comprises an additional step of machining the first or second space between the inner flange and the outer flange along a plane parallel to the median plane using a milling tool.

[0013] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0014] [Fig-1] [Fig.l] is a partial schematic representation of the principle of a trade to weave comprising an output lever according to the invention;

[0015] [Fig.2] [Fig.2] is a larger scale view of detail II of [Fig.l], the insert A) corresponds to a front view and insert B) to a perspective view,

[0016] [Fig.3] [Fig.3] is a partial section along line III-III in [Fig.2];

[0017] [Fig.4] [Fig.4] is a larger scale view of detail IV in [Fig.3];

[0018] [Fig.5] [Fig.5] is a view similar to insert A) of [Fig.2], the cam and the rollers being omitted;

[0019] [Fig.6] [Fig.6] is a schematic representation of the principle of the steps of a manufacturing method in accordance with the invention;

[0020] [Fig.7] [Fig.7] is a view similar to insert B) of [Fig.2] for a lever in accordance with a second embodiment of the invention.

[0021] The loom M shown in [Fig.l] comprises several heddle frames 2 of which only one is shown. The different heddle frames 2 of the loom M are driven by a vertical oscillation movement represented by the double arrow F1 and printed by a cam weaving mechanism 4. The output levers 6 of the cam weaving mechanism 4, of which only one is shown, each drive a pulling mechanism which actuates a frame and which is made up of a transmission connecting rod 8 associated with bent levers 10 connected to each other and to the heddle frame 2 by connecting rods 12.

[0022] The levers 6 are provided in a number equivalent to the number of heald frames 2 and pivotally mounted, as represented by the double arrow F2, around a lever shaft 14 supported by the frame 16 of the cam mechanism 4 and protected by a cover 18. The lever shaft 14 defines a main axis XI of the cam armour mechanism 4. Each output lever 6 is placed along the lever shaft 14 in a division whose width is fixed and equal to 12 millimetres.

[0023] The lever shaft 14 has ten divisions.

[0024] The cam armor mechanism 4 comprises several complementary cams 20, only one of which is shown and which each define two conjugate tracks 20A and 20B on which two follower rollers 22A and 22B supported by an output lever 6 respectively bear.

[0025] Each output lever 6 comprises a flat body 24 made of steel. The flat body 24 is cut from a sheet of constant thickness. The flat body 24 supports at its end 24A a clip 26 making it possible to connect the output lever 6 to the transmission connecting rod 8.

[0026] The flat body 24 defines a bore 24B for mounting on the shaft of the levers 14. As illustrated in the example of the figures, the bore 24B receives a roller bearing 28. In variants not shown, the bore 24B receives a ball bearing or a bushing.

[0027] The flat body 24 also comprises a first external face 24C and a second external face 24D. The external faces 24C and 24D are opposite and define between them a median plane PI perpendicular to the main axis XL

[0028] The flat body 24 also comprises a first inner flange 30A in one piece with the flat body 24. A first outer flange 32A is attached to the first outer face 24C of the flat body 24 opposite the first inner flange 30A. The first outer flange 32A is a piece of steel of constant thickness, this thickness being measured along the main axis XI when the outer flange 32A is integral with the flat body 24. The first outer flange 32A is of rounded triangular shape visible in the insert A) of [Fig.2].

[0029] The first follower roller 22A is held in a first space provided between the first outer flange 32A and the first inner flange 30A.

[0030] The flat body 24 comprises a second inner flange 30B in one piece with the flat body 24. A second outer flange 32B is attached to the second outer face 24D of the flat body 24 opposite the second inner flange 30B. The second outer flange 32B is similar to the first outer flange 32A. The second outer flange 32B is a piece of steel, of constant thickness and of rounded triangular shape.

[0031] The second follower roller 22B is held in a second space provided between the second outer flange 32B and the second inner flange 30B.

[0032] The first follower roller 22A and the second follower roller 22B advantageously have the same structure, or are even identical. The follower roller 22A is mainly described below, this description being transposable to the roller 22B.

[0033] The follower roller 22A, all of the elements of which are visible in [Fig. 3], comprises an inner ring 220 which has a disc shape centered on a roller axis X22, an outer ring 222 and rolling elements 224 interposed, radially to the roller axis X22, between the inner ring 220 and outer ring 222, so that the outer ring 222 is free to rotate relative to the inner ring 220 around the corresponding roller axis X22. When the follower roller 22A is received in the space provided between the first outer flange 32A and the first inner flange 30A, in an operating position, the roller axis X22 is parallel to the main axis XL

[0034] The rolling elements 224, which are rollers in the illustrated example, are held axially relative to the roller axis X22 by two flanks 226, made of sheet metal, located on either side of the inner ring 220 along the roller axis X22.

[0035] The outer ring 222 has a contact surface 222A which is radial to the roller axis X22 and is configured to be in contact with the track 20A of the cam 20.

[0036] Two holes are provided on the outer flange 32A, on the inner flange 30A, on the flanks 226 of the roller 22A and on the inner ring 220 of the roller 22A to receive two fixing members 229 of the roller 22A to the flat body 24. In the example illustrated, the fixing members 229 are so-called “roller” rivets. Each roller rivet 229 is centered on an axis parallel to the roller axis X22, each roller rivet 229 is radially offset from the roller axis X22.

[0037] Preferably, two roller rivets 229 secure each follower roller 22A, 22B to the flat body 24. In other variants not shown, a roller rivet 229 fixes each follower roller 22A, 22B to the lever 6 or more than two roller rivets 229 secure each follower roller 22A, 22B to the lever 6.

[0038] The follower rollers 22A, 22B have an outside diameter D22 equal to 88 millimeters. The outside diameter D22 is the diameter of the contact surface 222A of each roller 22A, 22B.

[0039] The first outer flange 32A and the second outer flange 32B are so lidarized to the flat body 24 by rivets 40. In this embodiment and according to an advantageous but not mandatory aspect of the invention, the rivets 40 are perforating rivets. In other words, the rivets 40 are capable of perforating the elements in which they are positioned without significantly deforming themselves. To do this, the perforating rivets 40 are, in the example illustrated, made of hardened steel, while the outer flanges 32A, 32B and the flat body 24 are made of steel. Any other grade of steel or steel alloys which includes for example manganese, nickel, carbon, molybdenum can be used to produce a perforating rivet 40, without departing from the scope of the invention, insofar as this perforating rivet 40 is less ductile than the outer flanges 32A, 32B and the flat body 24.

[0040] Advantageously, the outer flanges 32A and 32B have identical geometries and are fixed in a similar manner by perforating rivets 40 on the flat body 24.

[0041] The following describes mainly the first outer flange 32A and one of the perforating rivets 40, this description being transposable to the second outer flange 32B and to all of the perforating rivets 40.

[0042] The structure and positioning of the perforating rivets 40 are shown in detail in Figures 3 and 4.

[0043] As seen in [Fig.2], two perforating rivets 40 fix the outer flange 32A on the flat body 24. Each perforating rivet 40 defines an outer peripheral surface S40, of contact between the perforating rivet 40 and the elements in which the perforating rivet 40 is inserted, and a rivet axis X40. When the rivet 40 is placed in the elements 24 and 32A, the rivet axis X40 is parallel to the main axis XL

[0044] The rivet 40 comprises a rivet body 42 in the form of a solid of revolution around the rivet axis X40. In the example illustrated, the rivet body 42 is of generally cylindrical shape. In a variant not shown, the rivet body 42 is of frustoconical shape.

[0045] The perforating rivet 40 first penetrates into the outer flange 32A then into the flat body 24 so that the rivet body 42 extends along the rivet axis X40 between a rivet head 44 flush with an outer face S32A of the outer flange 32A and a rivet foot 46 flush with the outer face 24D of the flat body 24.

[0046] In a variant not shown, the perforating rivet 40 first penetrates into the flat body 24, the rivet head 44 then being flush with the external face 24D of the lever body and the rivet foot 46 with the external face S32A of the external flange 32A. In general, the first element is the element defined among the flat body 24 and the flange 32A, such that the rivet head 44 is flush with an external face of the first element and the second element is the element defined such that the rivet foot 46 is flush with an external face of the second element.

[0047] In a variant not shown, the inner flange 30A and / or the inner flange 30B are attached to the body 24 of the lever 6.

[0048] The height H40 of the perforating rivet 40, measured parallel to the rivet axis X40, is equal to the cumulative thickness of the flat body 24, of thickness e24 equal to 6 millimeters, and of the outer flange 32A, of thickness e32 equal to 5.5 millimeters, such that the perforating rivet 40 does not protrude from the output lever 6 and thus the maximum thickness e6, measured along the main axis XI, of the output lever 6 is less than the width of a division of the cam armor mechanism 4.

[0049] The maximum thickness of the output lever 6 is preferably configured to leave sufficient clearance between the multiple output levers 6 of the cam armor mechanism 4 to avoid any interference during operation, which would cause premature wear of the cam armor mechanism 4.

[0050] The rivet body 42 comprises an outer peripheral surface S42. When the perforating rivet 40 is positioned within the first and second elements, the first element being, in the illustrated example, the outer flange 32A and the second element being the flat body 24, the outer peripheral surface S42 of the rivet body 42 comprises a first outer peripheral surface portion S42A received in the first element and a second outer peripheral surface portion S42B received in the second element. The first outer peripheral surface portion S42A and the second outer peripheral surface portion S42B are concentric and of the same diameter.

[0051] The rivet body 42 has a diameter D42. The diameter D42 of the rivet body 42 is also by definition the diameter of the perforating rivet 40. The diameter D42 of the perforating rivet 40 is advantageously greater than the cumulative thickness e24+e32, measured along the rivet axis X40, of the flat body 24 and the outer flange 32A. In this way, the area of ​​the peripheral external surface S40 of the perforating rivet is large compared to its height, which allows optimal guidance of the perforating rivet 40 in the outer flange 32A and in the flat body 24 and good anchoring of the perforating rivet 40 in the outer flange 32A and the flat body 24. In addition, during use of the loom M, the forces exerted on the connection between the outer flange 32A and the flat body 24 will be distributed over a large contact surface, namely the surface S40.The rivet head 44 is of truncated cone shape, with a maximum diameter D44, and comprises a side wall S44A converging towards the rivet foot 46. The maximum diameter D^ of the rivet head 44 is strictly greater than the diameter D42 of the rivet body 42. The truncated cone side wall S44A is defined by an apex angle a. The apex angle a is less than 90°, preferably less than 60°, more preferably less than 40°.

[0052] In a variant of the invention not shown, the vertex angle a is greater at 90°.

[0053] The truncated cone shape of the rivet head 44 increases the contact surface between the outer flange 32A and the perforating rivet 40 and allows better mechanical retention of the perforating rivet 40 in the outer flange 32A.

[0054] The rivet head 44 also includes a centering hole 44B allowing centering of the rivet during the manufacturing process of the output lever 6.

[0055] The rivet foot 46 comprises an end face 46A perpendicular to the rivet axis X40. A cylindrical edge 46B, joining the end face 46A and the outer peripheral surface S40 of the perforating rivet 40, forms a right angle. Thanks to this cylindrical edge 46B joining at a right angle, the perforating rivet 40 can cleanly perforate the outer flange 32A and the flat body 24 without deforming.

[0056] By construction, the outer peripheral surface S40 comprises the outer peripheral surface S42 of the rivet body 42, the frustoconical side wall S44A of the rivet head 44 and the cylindrical edge 46B of the rivet foot 46.

[0057] A first groove 48 is formed on the external peripheral surface S40 of the perforating rivet 40. In the example illustrated, the first groove 48 is formed around the rivet foot 46.

[0058] The first groove 48 has a depth P48 measured perpendicular to the rivet axis X40 between the peripheral external surface S42 of the rivet body 42 and the bottom of the groove 48. The depth P48 of the groove 48 is greater than 0.2 millimeters, preferably greater than 0.4 millimeters, more preferably greater than 0.5 millimeters.

[0059] P2 is a reference plane intersecting with the first groove 48 and perpendicular to the rivet axis X40. The reference plane P2 is arranged at a distance d, measured along the rivet axis X40, from the external face 24D of the flat body 24. The distance d is less than 3 millimeters, preferably less than 2 millimeters, more preferably less than 1 millimeter.

[0060] The flat body 24 comprises, on its second external face 24D, a driving imprint 50. The driving imprint 50 is made so that a portion of the flat body 24 of a shape complementary to the groove 48 forms a bead 52, by driving in the portion of the material constituting the flat body 24 and which is initially present at the location of the driving imprint 50. The bead 52 of the flat body 24 is received in the groove 48 of the perforating rivet 40. In other words, the first groove 48 being formed around the rivet foot 46, the first groove 48 receives a portion of the second element 24 forming a bead 52 of a shape complementary to the first groove 48 and the external face of the second element comprises a driving imprint 50 of the portion of the second element which has been moved to form the bead 52.

[0061] The cooperation between the first groove 48 and the bead 52 allows robust retention of the perforating rivet 40 in the outer flange 32A and the flat body 24.

[0062] In variants not shown, the bead 52 does not occupy all the volume available in the first groove 48.

[0063] The driving imprint 50 is centered on the rivet axis X40 and is annular around the rivet axis X40. The driving imprint 50 has an inner diameter D50 measured perpendicular to the rivet axis X40. The inner diameter D 50 of the driving imprint 50 is equal to the diameter D42 of the rivet body 42.

[0064] In a variant not shown, the internal diameter D50 of the driving imprint 50 is greater than the diameter D42 of the rivet body 42.

[0065] The driving imprint 50 defines a bottom 50A. The bottom 50A of the driving imprint 50 is located, along the rivet axis X40, between the first groove 48 and the external face 24D of the flat body 24.

[0066] The driving imprint 50 has a depth P50 measured along the rivet axis X40 between the bottom 50A of the driving imprint 50 and the external face 24D of the flat body 24. The depth P50 of the driving imprint 50 is greater than 0.5 millimeters, preferably greater than 0.8 millimeters, more preferably greater than 1 millimeter.

[0067] C denotes a circle circumscribed to the driving imprint 50, which is visible on the insert B of [Fig.2]. Rc denotes the radius of the circumscribed circle C. R42=D42 / 2 denotes the radius of the perforating rivet 40. A ratio between the radius Rc of the circumscribed circle C and the radius R42 of the perforating rivet 40 is greater than 1.25, preferably greater than 1.5, more preferably greater than 2. This dimension ratio allows the driving in of a sufficient portion of material of the flat body 24 to form the bead 52 cooperating with the groove 48.

[0068] The driving imprint 50 makes it possible to provide enough material for the bead 52 to cooperate with the groove 48 to allow the anchoring of the perforating rivet 40 in the flat body 24, bearing by its rivet head 44 against the flange 32A. To ensure the mechanical strength of the flat body 24 which includes the driving imprint 50, it is necessary for the flat body 24 to extend beyond the driving imprint 50. More precisely, the flat body 24 extends, at least, over a semi-circular zone with a radius greater than 1.5 times the radius of the perforating rivet 40, preferably greater than 2 times the radius of the perforating rivet 40, more preferably greater than 3 times the radius of the perforating rivet 40, around the rivet axis X40. This minimum dimension of the flat body 24 around the rivet axis X40 ensures that there is sufficient material around the driving imprint 50 so as not to weaken the output lever 6 when the perforating rivet 40 is put in place.

[0069] Each perforating rivet 40 makes it possible to connect the outer flange 32A to the flat body 24 is distant from the geometric center of the corresponding roller 22A, that is to say from its roller axis X22, by a distance D measured in a plane parallel to the median plane PI and corresponding to the distance between the axes X22 and X40. Advantageously, the distance D is less than 80 millimeters, preferably less than 70 millimeters, more preferably less than 65 millimeters.

[0070] The quality of the connection between the outer flange 32A and the flat body 24 obtained by the perforating rivets 40 makes it possible to place the outer flanges 32A, 32B as close as possible to the roller axes X22 so that the overlap zone 36 which corresponds to the zone where the outer flange 32A, 32B and the flat body 24 are in contact is minimized. The minimization of this overlap zone 36 makes it possible to use outer flanges 32A, 32B of reduced size, which reduces manufacturing costs.

[0071] The method of manufacturing an output lever 6 comprising external flanges 32A, 32B secured by means of perforating rivets 40 as described previously is now described.

[0072] The flat body 24 of the output lever 6 and the outer flanges 32A and 32B are obtained in a known manner by finely cutting steel sheets.

[0073] The assembly of the outer flanges 32A, 32B on the flat body 24 of the output lever 6 is carried out in several steps within an external press tool P having several tools. These steps are shown in [Fig.6].

[0074] The external press tool P comprises two blank holders 60A, 60B, two punches 62A, 62B and two dies 64A, 64B. In the example illustrated in [Fig. 6], the first external flange 32A is secured to the flat body 24 by means of two perforating rivets 40 which are mounted in parallel and in a synchronized manner in the press tool P.

[0075] The orientation of the representation of the hold-down clamps 60A, 60B of the press tool P in [Fig. 6] is not limiting. The hold-down clamp 60A may be arranged above the hold-down clamp 60B relative to the ground, or below the hold-down clamp 60B relative to the ground, or the hold-down clamps may be oriented such that the axis X40 is parallel to the ground.

[0076] The side clamps 60A, 60B are configured to hold the flat body 24 and the outer flange 32A in contact and in a fixed position. In the example illustrated, the side clamps 60A and 60B are parallelepipedal and are in contact respectively with the outer flange 32A and the flat body 24 by means of flat surfaces. In variants not shown, the side clamps 60A, 60B have different geometries such as for example a curved contact surface.

[0077] The punches 62A, 62B are configured to each guide a perforating rivet 40 during the cutting step and the driving step.

[0078] Each die 64A and 64B is configured to push back a portion of the flat body 24 towards the flange 32A when the perforating rivet is in place in the elements 32A and 24, to form the bead 52 of complementary shape to the groove of the corresponding perforating rivet 40. The dies 64A and 64B are aligned respectively with the punches 62A and 62B.

[0079] The first step shown in insert A) of [Fig. 6] is a positioning step. The flat body 24 and the outer flange 32A are positioned relative to each other so as to overlap to form, after manufacture, the overlap zone 36. The flat body 24 and the outer flange 32A are also positioned in the outer press tool P between the two side clamps 60A and 60B and so that the punches 62A and 62B are opposite the desired locations of the perforating rivets 40.

[0080] The second step is a cutting step. This cutting step is shown in insert B) of [Fig.6]. A force F3 is applied by the press P along the rivet axis X40 to the punches 62A and 62B in a synchronized manner. The punches 62A and 62B each push a perforating rivet 40 along the rivet axis X40 so as to cut the first element, here the outer flange 32A, in its thickness and then to cut the second element, here the flat body 24, in its thickness. Advantageously, each punch 62A, 62B is engaged at the rivet head 44 of each rivet 40 in the central centering hole 44B of this rivet.

[0081] The third step is a driving step, during which each perforating rivet 40 is driven until the rivet foot 46 is flush with the external face 24D of the flat body 24.

[0082] The fourth step is a pushing step and is shown in insert C) of [Fig. 6]. A force F4 is applied along the rivet axis to each die 64A, 64B so as to push back a portion of the flat body 24 to form a bead 52 of a shape complementary to the groove 48 of the corresponding perforating rivet 40. Each die 64A, 64B marks an imprint 50 around the rivet foot 46 on the external face 24D of the flat body 24.

[0083] The method mentioned above is implemented for securing each of the flanges 32A and 32B with the flat body 24.

[0084] An output lever 6 is thus obtained on which the outer flanges 32A and 32B are secured to the flat body 24 by means of perforating rivets 40. The installation of the perforating rivets 40 without pre-drilling and the fact that the assembly is simultaneous with the cutting step ensures that there is no play between the perforating rivets 40, the outer flanges 323A and 32B and the flat body 24. The mechanical strength of the output levers 6 during use of the weaving loom M is greatly reinforced.

[0085] Once the outer flanges 32A, 32B are assembled on the flat body 24, a yoke space 70 is machined by a milling tool at the level of the space intended for receive the rollers 22A and 22B on the flat body 24 and on the flanges 32A, 32B. The yoke space 70 is visible by tearing in [Fig.5] and is delimited by a machining step 71.

[0086] More precisely, an internal surface of the outer flange 32A facing the roller 22A is machined in a plane parallel to the median plane PI so as to create a hollow housing 70A extending over the internal surface. Similarly, the external surface 24C of the flat body 24 facing the roller 22A is machined in a plane parallel to the median plane PI so as to create a hollow housing 70B extending over the external surface 24C. The union of the hollow housings 70A and 70B forms the yoke space 70.

[0087] Similarly, the outer flange 32B and the outer surface 24D of the flat body 24 are machined to form a yoke space 70 receiving the roller 22B.

[0088] Once the yoke spaces 70 have been machined opposite each roller 22A, 22B, the rollers 22A and 22B are put in place and riveted by two rivets 229 in the outer flanges 32A, 32B and in the flat body 24.

[0089] In a variant not shown of the method of the invention, in a step prior to driving the rivet, only the outer flange 32A, 32B is positioned in the outer tooling of the press P. Then, the outer flange 32A, 32B is perforated by the perforating rivets 40. The disc of material resulting from this perforation is removed from the press tooling P. Once this step has been carried out, the flat body 24 and the outer flange 32A, 32B are stacked and the flat body 24 is in turn perforated by the perforating rivets 40 through the hole resulting from the previous perforation of the outer flange 32A, 32B.

[0090] The assembly method described above is compatible with a stack of more than two elements. This assembly method is thus compatible, for example, with the assembly of an output lever 6 which comprises, for each follower roller, two external flanges attached to the flat body.

[0091] The output lever 6, as previously described, is particularly compatible with an armor mechanism described in CN215800175.

[0092] A second embodiment of an output lever 6' is shown in [Fig.7]. In the following description, elements similar to those of the first embodiment bear the same references and are not described in detail. If a reference is mentioned in the description without being shown in a figure or shown in a figure without being mentioned in the description, it designates the same element as that bearing the same reference in the first embodiment. In the following, we mainly describe what distinguishes this second embodiment from the previous one.

[0093] The output lever 6' comprises outer flanges 80A of a different shape from that of the outer flanges 32A, 32B of the first embodiment. Only the outer flange 80A opposite the roller 22A is visible in [Fig.7]. The perforating rivets 40 allowing the external flanges 80A to be fixed on the flat body 24 of the lever 6 are positioned differently compared to the first embodiment.

[0094] The outer flange 80A is of rounded triangular shape and comprises a tab 81A. A notch 82A which defines an opening between the roller 22A and the flat body 24 is made in the outer flange 80A.

[0095] The tab 81A extends between the notch 82A and the central bore 24B along a lubrication axis X2.

[0096] Dg is the distance measured in the median plane PI between the roller axis X22 and the main axis XL. L81 is the length of the tab 81A along the axis X2 from the bottom of the notch 82A on the axis X2 and the end B81 of the tab 81A. A ratio between the length L81 of the tab 81A and the distance Dg between the roller axis X22 and the main axis XI is greater than 2 / 3.

[0097] The tab 81A allows the oil of the cam armour mechanism 4 projected around the roller 22A to be guided through the notch 82A towards the central bore 24B receiving the shaft of the levers 14. This supply of oil is beneficial to the operation of the output levers 6 and the shaft of the levers 14 over time.

[0098] The assembly of this output lever 6' is carried out according to the same method as the assembly of the output lever 6 of the first embodiment.

[0099] For both embodiments, in a variant of the invention not shown, the first groove 48 is formed on the external peripheral surface S42 of the rivet body 42 around the rivet head 44 and receives a bead of the first element of a shape complementary to the first groove. In this configuration the reference plane P2 is at a distance d along the rivet axis X40 from the external surface of the first element.

[0100] In a variant of the invention not shown, the first groove 48 is formed around the rivet foot as described previously and a second groove is formed on the external peripheral surface S42 of the rivet body 42 near the rivet head 44. The second groove receives a bead of the first element of complementary shape to the second groove. Each groove is linked to a driving impression 50. The driving impression 50 linked to the second groove is produced by the die 64A, 64B along the axis X40 of the perforating rivet 40 comprising two grooves 48. The driving impression linked to the first groove is produced by a movable die in the blank holder 60A.

[0101] In another variant not shown, the driving impressions 50 associated with the two grooves 48 are produced one by one by the die 64A, 64B along the axis X40 of the perforating rivet 40, by turning over the assembly of the external flanges 32A and 32B and the flat body 24, between the two stages of stamping the two driving impressions 50.

[0102] In variants of the invention not shown, other geometries and positions grooves provided on the external peripheral surface of the perforating rivets 40 are possible.

[0103] In a variant of the invention not shown, each outer flange 32A, 32B is fixed to the flat body 24 by means of two perforating rivets 40 such that a first perforating rivet 40 is first inserted into the outer flange 32A, 32B then into the flat body 24 and a second perforating rivet 40 is first inserted into the flat body 24 then into the outer flange 32A, 32B. In this configuration, the flat body 24 and the outer flange 32A, 32B each have a driving imprint 50.

[0104] In variants not shown, the shape of the perforating rivet 40 may be different, in particular the perforating rivet 40 may be hollow or have a head of alternative shape.

[0105] In a variant of the invention, not shown, the lever body and the flanges are pre-drilled and the rivets are driven in and the beads are formed in the rivet grooves to assemble the first and second elements, without a prior cutting step by the rivet. In this case, the rivets are not perforating rivets. Thus, the invention covers the case where the rivets have not perforated the elements in which they are positioned, these elements having been one or the other or both perforated beforehand. The invention also covers the case where the perforating rivets have perforated one or the other or both of the elements partially, for example in the case where these elements have been pre-drilled to a diameter smaller than that of the rivets.

[0106] In another variant of the invention, not shown, the first inner flange 30A and / or the second inner flange 30B is attached to the lever body 24. The rivet head 44 is flush with the outer face of the inner flange and the rivet foot 46 is flush with the outer face of the outer flange. The first and second elements with which the rivet head 44 and the rivet foot 46 are flush are then, on the one hand, the first or second outer flange 32A, 32B and, on the other hand, the first or second inner flange 30A, 30B, or vice versa.

[0107] In another variant of the invention not shown, the yoke spaces are not machined.

[0108] As far as technically feasible, the embodiments and variants mentioned above can be combined with each other.

Claims

1. Claims Output lever with follower rollers (22A, 22B) of a cam armor mechanism (4) comprising: - a flat body (24) intended to support an articulation (26) with a transmission rod (8) of the oscillating movement of the output lever (6) to a stringer frame (2) and comprising: • a first face (24C) and a second face (24D) opposite each other and defining between them a median plane (PI), • a bore (24B) centered on a main axis (XI) intended to receive a bearing (28) or a bushing mounted on a shaft of the levers (14) of the cam armor mechanism (4), - a first internal flange (30A) in one piece with the body (24) or attached to the second face (24D) of the lever body (24); - a second internal flange (30B) in one piece with the body (24) or attached to the first face (24C) of the lever body (24); - a first outer flange (32A), attached to the first face (24C) of the lever body (24), opposite the first inner flange (30A); - a second outer flange (32B), attached to the second face (24D) of the lever body (24), opposite the second inner flange (30B); - a first roller (22A) intended to follow a first track (20A) of a cam (20) of the armor mechanism (4) and held in a first space (70) formed between the first outer flange (32A) and the first inner flange (30A); - a second roller (22B) intended to follow a second track (20B) of the cam (20) of the armor mechanism (4) and held in a second space (70) formed between the second outer flange (32B) and the second inner flange (30B); - at least two rivets (40) for fixing at least one of the outer flanges (32A, 32B) to the flat body (24), the rivets (40) passing through the body of the lever (24) and the outer flange (32A, 32B), characterized in that each rivet (40) comprises: - a rivet body (42) in the form of a solid of revolution around a rivet axis (X40) extending between: • a rivet head (44) flush with an external face (24C, 24D, S32A) of a first element among the external flange (32A, 32B) and the internal flange (30A, 30B, 24), • a rivet foot (46) flush with an external face (24C, 24D, S32A) of the second element among the external flange (32A, 32B) and the internal flange (30A, 30B, 24); - at least one first rivet groove (48) formed on an external peripheral surface (S40) of the rivet (40) in which a portion of the first (32A, 32B, 30A, 30B, 24) or of the second element (32A, 32B, 30A, 30B, 24) forms a bead (52) of a shape complementary to the first groove (48); in that the first element and / or the second element (32A, 32B, 30A, 30B, 24) comprises, on its external face (S32A, 24C, 24D), a driving imprint (50), of the portion of the first or second element (32A, 32B, 24) which forms the bead (52), and in that the driving imprint (50) is centered on the rivet axis (X40).

2. Output lever according to claim 1, characterized in that the rivet head (44) has a maximum diameter (D44) strictly greater than the diameter (D42) of the rivet body (42) and in that the first groove (48) is formed around the rivet foot (46).

3. Output lever according to claim 2, characterized in that the rivet head (44) comprises a frustoconical side wall (S44A) converging towards the rivet foot (46), and in that an angle at the apex (a) of the frustoconical side wall (S44A) is less than 90°, preferably less than 60°, preferably less than 40°.

4. Output lever according to one of the preceding claims, characterized in that a second groove is provided on the external peripheral surface (S40) of the rivet (40), around the rivet body (42) near the rivet head (44), in that the first groove (48) is provided on the external peripheral surface (S40) of the rivet (40), around the rivet foot (46), in that the first groove (48) receives a bead (52) of the second element (24, 32A, 32B), of complementary shape to the first groove (48), and in that the second groove receives a bead of the first element (24, 32A, 32B), of complementary shape to the second groove.

5. Output lever according to one of the preceding claims, characterized in that the depth (P48) of the first groove or of at least one of the grooves is greater than 0.2 millimeters, preferably greater than 0.4 millimeters, more preferably greater than 0.5 millimeters.

6. Output lever according to one of the preceding claims, characterized in that the driving imprint (50) is annular, in that it has an internal diameter (D50) equal to the diameter (D42) of the rivet body (42) and in that a bottom of the imprint (50A) is arranged, along the rivet axis (X40), between the first groove (48) of the perforating rivet (40) and the external face (S32A, 24C, 24D) of the first and / or second element (32A, 32B, 24) which comprises the driving imprint (50).

7. Output lever according to one of the preceding claims, characterized in that a ratio between the radius (Rc) of the circumscribed circle (C) of the driving imprint (50) and the radius of the perforating rivet (R^) is greater than 1.25, preferably greater than 1.5, more preferably greater than 2.

8. Output lever according to one of the preceding claims, characterized in that the depth (P50) of the driving imprint (50), measured along the rivet axis (X40), is greater than 0.5 millimeters, preferably greater than 0.8 millimeters, more preferably greater than 1 millimeter.

9. Output lever according to one of the preceding claims, characterized in that the external face (24C, 24D, S32A) of the first and / or second element (32A, 32B, 24) which comprises the driving imprint (50) extends in a semi-circular zone centered on the rivet axis (X40) with a circle radius preferably greater than or equal to 1.5 times the radius (R42) of the rivet (40), preferably greater than or equal to 2 times the radius (R42) of the rivet (40) and preferably still greater than or equal to 3 times the radius (R42) of the rivet (40).

10. Output lever according to one of the preceding claims, characterized in that a reference plane (P2) intersecting with the first groove (48) is arranged at a distance (d) from the external face (24C, 24D, S32A) of the first or second element (32A, 32B, 24), measured along the rivet axis (X40), less than 3 millimeters, preferably less than 2 millimeters, more preferably less than 1 millimeter.

11. Output lever according to one of the preceding claims, characterized in that the rivet foot (46) comprises an end face (46A) perpendicular to the rivet axis (X40) and in that a cylindrical edge (46B) joining the end face (46A) and the external peripheral surface (S40) of the rivet (40) forms a right angle.

12. Output lever according to one of the preceding claims, characterized in that the diameter (D42) of the rivet (40) is greater than the cumulative thickness (e24+e32), measured along the rivet axis (X40), of the flat body (24) of the lever (6) and of an external flange (32A, 32B).

13. Output lever according to one of the preceding claims, characterized in that the outer flange (80A) comprises a tab (81 A) which extends along a lubrication axis (X2) and configured to guide lubricant from a roller (22A, 22B) towards the bore (24B) of the lever body (24).

14. Output lever according to one of the preceding claims, characterized in that the outer peripheral surface (S42) of the rivet body (42) comprises a first outer peripheral surface portion (S42A) received in the first element (32A, 32B, 24) and a second outer peripheral surface portion (S42B) received in the second element (24, 32A, 32B), and in that the first outer peripheral surface portion (S42A) and the second outer peripheral surface portion (S42B) are concentric and of the same diameter.

15. Output lever according to one of the preceding claims, characterized in that each rivet is a perforating rivet (40).

16. Method of manufacturing an output lever (6) according to one of the preceding claims, characterized in that the manufacturing method comprises at least the following steps: - a) driving the rivet (40) until the rivet foot (46) is flush with the external face of the second element (24C, 24D, S32A), the rivet (40) being pushed by an external press tool (P) configured to exert a pushing force (F3) on the rivet (40) along the rivet axis (X40); and - b) pushing back a portion of the second element (32A, 32B, 24) to form a bead (52) of complementary shape to the groove (48) of the rivet (40) by means of an external die (64A, 64B) centered on the rivet axis (X40) and marking a driving imprint (50) around the rivet foot (46) on the external face of the second element (24C, 24D, S32A) and / or a portion of the first element (32A, 32B, 24) to form a bead (52) of complementary shape to the groove (48) of the perforating rivet (40) by means of an external die (64A, 64B) centered on the rivet axis (X40) and marking a driving imprint (50) around the rivet head (44) on the external face of the first element (24C, 24D, S32A).

17. Manufacturing method according to claim 16, characterized in that the manufacturing method comprises at least the following preliminary steps: - c) cutting, by means of the rivet (40) which is a perforating rivet, the first element (32A, 32B, 24) in its thickness, - d) cutting, by means of the perforating rivet (40), the second element (32A, 32B, 24) in its thickness, the perforating rivet (40) being pushed by means of the external press tool (P) along the rivet axis (X40).

18. Manufacturing method according to claim 17, characterized in that the manufacturing method comprises an additional step of positioning the second element (32A, 32B, 24) on the first element (32A, 32B, 24) at an overlap zone (36) in the external press tooling (P) after step c) and before step

19. O). Manufacturing method according to one of claims 17 and 18, characterized in that it comprises cutting, driving and pushing steps similar to steps a) to d) for a second rivet (40), which is a perforating rivet positioned at a distance from the first rivet (40).

20. Manufacturing method according to one of claims 16 to 19, characterized in that the manufacturing method comprises an additional step consisting of machining the first or second space (70) between the inner flange (30A, 30B) and the outer flange (32A, 32B) along a plane parallel to the median plane (PI) by means of a milling tool.

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