Opening mechanism and jacquard loom equipped with the same

Abstract

The present application relates to an opening mechanism and a jacquard loom equipped with an opening mechanism. The opening mechanism comprises at least one hook moving in a longitudinal direction, which hook can be held in place by a selection device comprising at least one electromagnet comprising a ferromagnetic core comprising at least a first pole face and a second pole face. The selection device further comprises a holding lever configured to hold the movable hook when the movable hook is in or close to its upper dead center position. The holding lever comprises a ferromagnetic armature which magnetically interacts with the first and second pole faces to control the angular position of the holding lever about a pivot axis, the armature comprising an outer attractive surface, and a non-magnetic body integral with the armature. The non-magnetic body of the holding lever comprises at least one abutment surface adjacent to the outer attractive surface. The outer attractive surface is distanced from the second pole face when the holding lever is in its position of contact with the electromagnet.

Description

Technical Field

[0001] The present invention relates to an shedding mechanism in a jacquard loom, and a jacquard loom equipped with such a mechanism. Background Technology

[0002] In jacquard looms, the shedding mechanism selectively lifts heddles, each heddle including an eyelet through which warp threads pass. Depending on the position of the hook attached to the upper end of each heddle, the yarn passing through its eyelet is positioned above or below the weft yarn moving by the loom. In practice, the shedding mechanism includes multiple movable hooks, each hook having a side nose adapted to engage with a vertically reciprocating cutter. Each movable hook is capable of interacting with a retaining member, which is part of the selection device as part of the shedding mechanism and is controlled by an electromagnet.

[0003] As described in EP-A-1413657, a retaining rod may include a metal armature that magnetically interacts with the two pole faces of an electromagnet, and the retaining rod is movable between a position away from the lower pole face of the electromagnet and a position in contact with the electromagnet, in which the retaining rod can be held in place due to the activation of the electromagnet. In this position, a portion of the metal armature of the retaining rod abuts against the lower pole face.

[0004] Similar structures are known from EP-A-0823501, EP-A-0851048, EP-A-0899367, EP-A-1619279 and EP-A-1852531, and these structures are generally satisfactory.

[0005] CN-U-210506675 also discloses a jacquard module equipped with two retaining rods, each retaining rod comprising a magnetoarmature surrounded by a wear-resistant sleeve portion. A short stub formed by the magnetoarmature abuts against a portion of a Y-shaped electromagnet without forming an air gap. Summary of the Invention

[0006] The purpose of this invention is to improve the accuracy and reliability of selection by the selection device by means of an opening mechanism that improves the accuracy of the air gap between the retaining rod and the electromagnet, thereby precisely controlling the magnetic attraction between these elements and the current supplied to the electromagnet.

[0007] Therefore, the present invention relates to a shedding mechanism for a jacquard loom, the mechanism comprising at least one movable hook, a cutter portion that moves the movable hook along the longitudinal direction between a bottom dead center position and a top dead center position, the hook being able to be held by a selection device when at or near the top dead center position, the selection device comprising at least:

[0008] - An electromagnet comprising a ferromagnetic core defining at least one first pole face and at least one second pole face, the pole faces being offset from each other along the longitudinal direction.

[0009] - A retaining rod configured to hold a movable hook when the movable hook is at or near its upper dead center position, the retaining rod being mounted to pivot about a swing axis between a position away from the electromagnet and a position in contact with the electromagnet, the swing axis being fixed relative to the electromagnet in the operating configuration of the mechanism, the retaining rod comprising:

[0010] A ferromagnetic armature, which magnetically interacts with the first and second pole faces to control the angular position of the retaining rod about the swing axis, includes an outer attraction surface that faces the second pole face when the retaining rod is in contact with the electromagnet.

[0011] • A non-magnetic body that is integral with the armature.

[0012] According to the present invention, the non-magnetic body of the retaining rod includes at least one stop surface, the stop surface being:

[0013] - Adjacent to the external attraction surface;

[0014] - When the retaining rod is in a position away from the electromagnet, it should be moved away from the electromagnet; and

[0015] -When the retaining rod is in contact with the electromagnet, it is in contact with the electromagnet.

[0016] At the same time, at the position where the retaining rod contacts the electromagnet, the external attraction surface is far away from the second pole surface.

[0017] Due to the present invention, the abutment surface defined by a non-magnetic body allows the outer attraction surface of the metal armature (adjacent to the metal armature) to be positioned relative to the second pole face of the electromagnet in a precise and repeatable manner at the contact position with the retaining rod. At the contact position, the air gap between the outer attraction surface and the second pole face is thus well controlled, and the magnetic attraction between the retaining rod and the electromagnet is also well controlled when the electromagnet is activated.

[0018] According to an advantageous but non-mandatory aspect of the invention, such an opening mechanism can be combined with one or more of the following features, employing any technically permissible combination.

[0019] - Each contact surface protrudes from the outer attraction surface along the direction of the electromagnet.

[0020] - Each contact surface is arranged along the longitudinal direction so as to be opposite to the swing axis relative to the external attraction surface.

[0021] - The armature extends longitudinally from the oscillation axis only to the connection area between the outer attraction surface and the abutment surface.

[0022] - The non-magnetic body of the retaining rod is a single piece and includes a selection surface and / or a ramp, the selection surface being capable of holding the movable hook at or near its dead point position, and the ramp being used to interact with the movable hook to move the retaining rod from its position away from the electromagnet to its position in contact with the electromagnet.

[0023] - When the retaining rod is in contact with the electromagnet, the abutting surface abuts against the second pole surface, which is the outer surface of the electromagnet's ferromagnetic core, protruding toward the retaining rod relative to the electromagnet's nonmagnetic frame.

[0024] - The length of the outer attraction surface, measured along a direction parallel to the longitudinal direction, is greater than the length of the abutment surface facing the second pole when the retaining rod is in contact with the electromagnet, the length of the abutment surface being parallel to the length measurement of the attraction surface.

[0025] - When the retaining rod is in contact with the electromagnet, the retaining rod does not hold the movable hook at or near the top dead center position.

[0026] - The electromagnet is attached and fixed in the housing of the mechanism, wherein the non-magnetic portion of the electromagnet integral with the ferromagnetic core includes a guide surface for guiding the retaining rod to pivot about the swing axis, the guide surface engaging with the retaining rod in a direction radial to the swing axis between the remote position and the contact position of the retaining rod, and wherein the guide surface is cylindrical, having a circular base, and centered on the swing axis.

[0027] - The non-magnetic body of the retaining rod includes a pin and a circumferential flange surrounding the pin, the flange being configured to receive support from a coil spring used to return the retaining rod to a position away from the electromagnet.

[0028] - The swing axis is arranged at the same height as the first polar surface along the longitudinal direction.

[0029] The armature of the retaining rod has a groove for receiving a guide shaft for pivoting the retaining rod between its position away from the electromagnet and its position in contact with the electromagnet, the guide shaft extending along the pivot axis, and the armature including an outer surface facing the first pole face and having a non-zero gap between the position away from the electromagnet and the position in contact with the electromagnet.

[0030] The mechanism includes a housing, a movable hook that moves within the housing, and an electromagnet mounted and fixed within the housing. A guide shaft for pivoting the retaining rod is formed on the housing or on the non-magnetic frame of the electromagnet.

[0031] - The ferromagnetic core of the electromagnet includes a middle section, around which windings are formed, and the first and second pole faces are arranged longitudinally on both sides of the middle section.

[0032] - The contact surface is formed by a non-magnetic material with a notched outer surface, and the notched outer surface is provided with grooves juxtaposed along the longitudinal direction.

[0033] According to another aspect, the present invention relates to a jacquard loom that includes the shedding mechanism described above.

[0034] This type of loom has the same advantages as shearing mechanisms. Attached Figure Description

[0035] The invention will be well understood from the following description of several embodiments of the sheathing mechanism and loom consistent with its principles, and its other advantages will become more apparent. These descriptions are given by way of example only and with reference to the accompanying drawings, in which:

[0036] Figure 1 This is a schematic diagram illustrating a jacquard loom conforming to the present invention, and incorporating the principle of an shedding mechanism conforming to the present invention;

[0037] Figure 2 It belongs to Figure 1 A perspective view of the electromagnetic core of the sheathing mechanism of a loom;

[0038] Figure 3 Is Figure 2 A perspective view of the electromagnet after an insulating frame is installed on the iron core.

[0039] Figure 4 It is based on Figure 3 The larger proportion of the cross section of the midplane IV;

[0040] Figure 5 Is Figure 3 A perspective view of a protectively molded electromagnet mounted on a visible frame;

[0041] Figure 6 yes Figure 5 The larger proportion of the cross section in the mid-plane VI;

[0042] Figure 7 It belongs to Figure 1 A perspective view of the retaining rod of the sheathing mechanism of a loom;

[0043] Figure 8 Is the retaining rod in Figure 7 Front view in the direction of arrow VIII;

[0044] Figure 9 yes Figure 6 and Figure 7The side view of the retaining rod shows two partial cross-sections, AA and BB.

[0045] Figure 10 yes Figure 1 A perspective view of the housing of the opening mechanism, wherein in the magnified detailed view, the area of ​​the housing is used to accommodate the electromagnet and the corresponding part of the housing cover;

[0046] Figure 11 This is a partial front view of the housing equipped with a selection device, which consists of an electromagnet, two retaining rods, and two movable hooks.

[0047] Figure 12 yes Figure 11 Detailed Figure X A larger scale view of II;

[0048] Figure 13 yes Figure 11 Detailed Figure X A larger scale view of III;

[0049] Figure 14 It is a larger proportion of the cross section, which corresponds to Figure 11 Line XIV-XIV in the middle belongs to Figure 1 The sheathing mechanism of the loom is stacked in the housing;

[0050] Figure 15 It is based on Figure 14 A portion of the cross-section of line XV-XV in the middle;

[0051] Figure 16 Is with Figure 11 The lower left portion of the partial view corresponds to the opening mechanism conforming to the second embodiment of the present invention;

[0052] Figure 17 Is with Figure 16 A similar view of an opening mechanism conforming to a third embodiment of the present invention;

[0053] Figure 18 Is with Figure 5 A similar partial perspective view of an electromagnet belonging to the opening mechanism according to the fourth embodiment of the present invention;

[0054] Figure 19 Is with Figure 16 A similar view of the opening mechanism conforming to the fourth embodiment of the present invention; and

[0055] Figure 20 Is with Figure 16 A similar view of an opening mechanism conforming to the fifth embodiment of the present invention. Detailed Implementation

[0056] exist Figure 1 In the jacquard loom M shown, the warp yarns 1 come from the warp beam 2. Each warp yarn 1 passes through the eye 3a of the heddle 3, which is designed to open the shed to allow the weft yarn to pass through, thereby forming the fabric T wound on the bobbin 4. Figure 1 Only two heddles, 3 and 3', are shown, with heddle 3 at the top and heddle 3' at the bottom. The lower end of each heddle is connected to the fixed frame of the loom M via a tension spring 5, while its upper end is integrated with the yoke 6.

[0057] The opening mechanism 7 associated with the electronic control unit 8 that controls it allows each yoke 6 to be raised more or less against the rebound force exerted by the spring 5.

[0058] As shown in the figure, regarding only the yoke 6 associated with the heddle 3, each yoke has an end 6a integral with the housing 10 of the opening mechanism 7. This yoke passes through the lip-nose 11 suspended on the cord 12. Both ends of the cord 12 are integral with two movable hooks 13, which can be selectively lifted by a blade 14 driven by alternating vertical oscillating movements of opposite phases. Figure 1 As indicated by arrow F1 in the diagram. Other configurations of the yoke, crease, and lip-nose area are also possible.

[0059] For clarity of the accompanying diagram, in Figure 1 Only a portion of the components of the opening mechanism 7 are shown in the image.

[0060] The shedding mechanism 7, also referred to as a "jacquard module," comprises a stack of multiple integral housings, such as eight housings. Each housing contains a selection device including an electromagnet and two retaining rods. Furthermore, two hooks 13 are longitudinally movable within each housing, i.e., along the longest dimension of the housing 10, and are vertical in the mounting configuration of this housing within the shedding mechanism 7 mounted on the loom M. These two movable hooks are preferably integrated with a single thread, for example... Figure 1 The lip and nose section 11 through which the yoke 6 passes is suspended on the 12 shown.

[0061] Each electromagnet 100 of the opening mechanism 7 includes Figure 2The diagram shows an exposed ferromagnetic core 102, a frame 104 made of non-magnetic material, a winding 106 wound around the middle portion of the core 102, a cover 108, and electrical contacts 110. The electrical contacts 110 are intended to connect to two cables (not shown) that connect the electromagnet 100 to the electronic control unit 8 and allow selective power supply to the electromagnet 100. The frame 104 and cover 108 together form the non-magnetic portion of the electromagnet 100. The winding 106 and electrical contacts 110 also belong to the non-magnetic portion of the electromagnet 100. "Non-magnetic" means that the magnetic susceptibility is very low, preventing the non-magnetic portion from magnetically interacting with the ferromagnetic portion.

[0062] The longitudinal axis is marked as Figure 2 The central electromagnet 100 has an axis X100 oriented from top to bottom. Figure 4 The horizontal axis of the electromagnet 100, oriented from left to right, is marked Y100. The axis indicating the thickness or depth of the electromagnet 100 is marked Z100, which is also the axis in the direction of the smallest dimension of the electromagnet 100. The axes X100, Y100, and Z100 together form a directly oriented orthogonal reference system. Figure 4 and Figure 6 They are along Figure 3 Central axis X100 direction and Figure 5 Cross-section in the opposite direction to the central axis X100.

[0063] Core 102 has a thickness e102 measured parallel to axis Z100, and this thickness is constant. Core 102 is generally I-shaped, having a longitudinal central rod 120 extending in a direction parallel to axis X100, and two transverse branches 122 and 124 extending primarily in a direction parallel to axis Y100. The longitudinal central rod 120 is the intermediate portion between the transverse branches 122 and 124.

[0064] The side ends of the upper transverse branch 122 form two upper pole surfaces S122 of the electromagnet 100. These first pole surfaces are concave and cylindrical in cross-section, defined on the edge of the core 102, with the circular cross-section centered on an axis A122 perpendicular to the main plane of the core 102. The axis A122 is parallel to the axis Z100. On the other hand, the side ends of the lower transverse branch 124 form two lower pole surfaces S124 of the electromagnet 100. These second pole surfaces S124 are arranged on the edge of the core 102, flat, and parallel to the axes X100 and Z100.

[0065] The first polar surface S122 deviates from the second polar surface S124 along the axis X-ray 100.

[0066] In the middle portion of the lower branch 124, a centering notch 126 is provided on the edge of the lower branch opposite to the center rod 120. The centering notch is located along the axis Y100 between and equidistant from the lower pole surfaces S124.

[0067] The frame 104 is overmolded around the core 102, which it partially surrounds. "Overmolding" refers to injecting material from the frame 104 into a mold in which the core 102 was previously placed, such that the material of the frame 104 surrounds the core 102 and attaches to it after curing. The frame 104 is made of a non-magnetic material, such as a thermoplastic polymer, and may be reinforced with fibers. Therefore, the frame 104 is integral with the core 102 and has a fixed position relative to the core 102.

[0068] like Figure 3 As shown, the frame surrounds the upper transverse branch 122 of the core 102, flush with surface S122. The frame 104 extends on both sides of the upper transverse branch 122 via flanges 142 and guide shafts 144 centered on corresponding axes A144. The two flanges 142 and the two shafts 144 are part of the frame 104, integral with the rest of the frame 104, particularly with the portion of the frame surrounding the upper transverse branch 122. In other words, each guide shaft 144 is non-removably connected to the frame 104, particularly to the adjacent flange 142. Axis A144 is parallel to axis Z100. Each axis A144 coincides with the central axis A122 of the adjacent upper pole surface S122. Therefore, each axis A144 is at the same longitudinal height as the adjacent upper pole surface S122. Each guide shaft 144 has a cylindrical external shape with a circular cross-section, and its outer peripheral surface is marked S144.

[0069] Frame 104 also defines a centering pin 146, which extends relative to the middle portion of the upper branch 122 and is centered on axis A146, which is parallel to axis A144 and axis Z100. Centering pin 146 is also cylindrical with a circular cross-section. Unlike guide shaft 144, it is hollow, while guide shaft is solid.

[0070] The frame 104 includes two bars 148 that cover the edges 120A and 120B of the central rod 120 perpendicular to the axis Y100, but do not cover the sides 120C and 120D of the central rod perpendicular to the axis Z100.

[0071] The frame 104 also includes feet 150 that cover the connection area between the rod 120 and the branch 124, as well as slats 152.

[0072] The lower transverse branch 124 protrudes from the frame 104 along the longitudinal direction of the ferromagnetic core 102 parallel to the axis X100 and along the transverse direction of the ferromagnetic core parallel to the axis Y100. In particular, the frame 104 does not extend at the height of the lower pole face S124.

[0073] Flange 142 is located near one end of each guide shaft 144 and extends annularly around it, connecting the shaft to the rest of the frame 104. Flange 142 is formed on the non-magnetic portion of the electromagnet 100. The annular surface of each flange 142, perpendicular to axis Z100 and facing the guide shaft 144 around which the flange is located, is designated S142. This surface S142 is perpendicular to the axis A144 of the adjacent guide shaft 144 and extends annularly around the guide shaft, i.e., more than 360°. Surfaces S142 and S144 are adjacent and perpendicular.

[0074] The peripheral surface of flange 142 is designated S'142. This surface is part of a cylinder having a circular base centered on the axis A144 of the adjacent guide shaft 144. Therefore, the peripheral surface S'142 of flange 142 is coaxial with the outer peripheral surface S144 of the adjacent guide shaft 144.

[0075] The surface S142 of the flange 142, together with the outer peripheral surface S144 of the adjacent guide shaft 144 and the upper pole surface S122 opposite thereto, defines a space for receiving Figures 7 to 9 The space V1 is a portion of the retaining rod 200, represented separately. More specifically, surface S144 radially defines space V1 in a direction converging toward axis A144. Surface S122 radially defines space V1 in a direction diverging from axis A144. Surface S142 axially defines space V1 in a direction from the free end 144E of shaft 144 toward adjacent flange 142 (i.e., here opposite to the direction of axis Z100).

[0076] The space V1 defined by the electromagnet 100 can be referred to as a partial receiving housing for the retaining rod 200.

[0077] Each guide shaft 144 is formed as a part of the electromagnet 100, and in particular is integral with the frame 104. This fact allows for a reduction in the positioning tolerance of the guide shaft relative to the ferromagnetic core 102, and more precisely, a reduction in the positioning tolerance between surfaces S144 and S122. This contributes to the accuracy of the geometric definition of space V1 and the accuracy of guiding the retaining rod 200 relative to the ferromagnetic core 102.

[0078] The winding 106 is manufactured by winding wire in the form of coils around a central rod 120 of a ferromagnetic core 102 equipped with bars 148. This winding is manufactured after a frame 104 has been overmolded onto the ferromagnetic core 102, such that the winding 106 contacts the sides 120C and 120D of the central rod 120, but is separated from the edges 120A and 120B by the bars 148. Each end of the wire constituting the winding 106 is connected to one of the two electrical contacts 110. The frame 104 then provides electrical insulation between the two electrical contacts 110, and between the core 102 and the two electrical contacts 110, including at their connections to the winding 106. Once the winding 106 is in place on the central rod 120 and connected to the electrical contacts 110, a cover 108 is applied to the components 102, 104, and 106 by low-pressure overmolding, forming a protective layer specifically for the winding 106. Figure 3 and Figure 5 The geometry of the cover 108 can be deduced through comparison. Then, the cover 108, winding 106, and electrical contacts are integrated with the iron core 102.

[0079] An orthogonal reference system X200, Y200, and Z200 is defined associated with each retaining rod 200, with axis X200 parallel to the maximum dimension of the rod 200; that is, it forms the longitudinal axis of the rod, the transverse axis Y200 parallel to the width of the rod, and the depth axis Z200 parallel to the thickness of the rod. When the retaining rod 200 is installed within the opening mechanism 7, axis X200 is oriented downwards.

[0080] The rod 200 includes an armature 202 made of a ferromagnetic material (e.g., pure iron) and a nonmagnetic body 204 integral with the armature 202. The armature 202 magnetically interacts with a first pole face and a second pole face S122, S124, as will be apparent from the following disclosure. The armature 202 extends parallel to axis X200 between a first longitudinal end 206 and a second longitudinal end 208. The first longitudinal end 206 defines a first housing 210 extending through its thickness and having a circular cross-section centered on an axis A210 parallel to axis Z200. The peripheral surface of housing 210 is designated S210, which is the inner surface of the first end 206. The outer peripheral surface of end 206 is designated S206. A portion S206A of the outer peripheral surface S206 has a circular base centered on axis A210, and this portion S206A itself forms the outer surface of the first longitudinal end 206.

[0081] The second longitudinal end 208 of the armature 202 defines a second housing 212 that extends through the armature along its thickness, and a nonmagnetic body 204 is anchored therein by means of a rod 214 that is integral with the rest of the nonmagnetic body 204 and extends through the housing 212.

[0082] In practice, the nonmagnetic body 204 is formed of a synthetic material, particularly a plastic material, such as a thermoplastic polymer, possibly reinforced with fibers, which is overmolded onto the metal armature 202 by filling the second housing 212, thereby forming a rod 214. Therefore, the nonmagnetic body 204 has a fixed position relative to the armature 202 and is movable with the armature 202. The nonmagnetic body 204 surrounds end 208 of the armature 202 and extends in the direction of the longitudinal axis X200, i.e., away from the first longitudinal end 206.

[0083] The non-magnetic body 204 forms a selection nose 216, a guide ramp 218, and a pin 220 around its entire periphery by a ring portion 222. The surface S216 of the selection nose facing the armature 202 and the first end 206 allows the movable hook 13 to be held in or near its dead point position by engaging a hole in the movable hook.

[0084] Along the transverse direction of the non-magnetic body 204, parallel to axis Y200, nose 216 and ramp 218 are located on one side of the body, while pin 220 and flange 222 are located on the other side of the body. Surface portion S206A is located on the same side of retaining rod 200 as pin 220.

[0085] The main body 204 also includes an abutment surface S204, which is designed to selectively contact the electromagnet 100 depending on the position of the retaining rod. The selective nose 216, guide ramp 218, and pin 220 are integrally formed with the abutment surface S204.

[0086] Along the longitudinal direction of rod 200, i.e., along axis X200, the abutment surface S204 is adjacent to the external attraction surface S208 formed by the second end 208 of armature 202. More specifically, the external attraction surface S208 is formed by a slice of the portion 208A of the second end that is not covered by the non-magnetic body 204. The abutment surface S204 and the external attraction surface S208 are adjacent because they share a common boundary.

[0087] As the armature 202 extends seamlessly between these surfaces, surfaces S206A and S208 exhibit electrical continuity. This is particularly due to the fact that, in this example, the armature 202 is monolithic.

[0088] The portion 208A of the defined external attraction surface S208 of end 208 is the part of armature 202 that is furthest from the first end 206.

[0089] Armature 202 extends from the first end 206 in the direction of axis X200 to the junction of the outer attraction surface S208 and the abutment surface S204. In other words, armature 202 does not extend significantly beyond portion 208A within the non-magnetic body 204.

[0090] The contact surface S204 is generally flat and parallel to axes X200 and Z200, and is equipped with transverse grooves 224 parallel to axis Z200, which are juxtaposed along the longitudinal direction of the rod parallel to axis X200. These grooves 224 have the effect that the surface S204 is not smooth but concave, because it is formed by juxtaposing strips of material separated by the grooves 224.

[0091] The deflectors are formed of a non-magnetic body 204 and are integral with the rest of the body. A first deflector 226 extends longitudinally around the non-magnetic body 204 at the same height as the abutment surface S204, but is opposite to the surface along the transverse axis Y200. Two other deflectors 228 and 230 are formed of the non-magnetic body 204 on the same side as the abutment surface S204, but at different heights along the longitudinal axis X200, located on opposite sides of the surface along this axis. More specifically, deflector 228 is located along the axis X200 between the first longitudinal end 206 and the abutment surface S204, while the second deflector 230 is located along the axis X200 between the abutment surface S204 and the pin 220. Connecting strips 232 connect the deflectors 228 and 230 along the longitudinal direction of the retaining rod 200. These connecting strips 232 are located on opposite sides of surfaces S204 and S208 along the axis Z200. Deflector 226 is connected to joint bar 232.

[0092] Therefore, deflectors 226, 228, and 230 are continuous with each other. Specifically, deflectors 228 and 230, as well as the connecting strip 232, form continuous edges around surfaces S204 and S208, such as... Figure 7 As observed in the direction of the middle arrow VIII, deflector 226 and selector nose 216 are located on the same side of the nonmagnetic body 204, while a pair of deflectors 228 and 230 are located on the same side as the abutment surface S204 and the external attraction surface S208. Furthermore, deflector 226 is located longitudinally (i.e., along the axis X200) between deflectors 228 and 230.

[0093] The opening mechanism 7 also includes one or more integral housings 300 as part of the housing 10. The number of integral housings 300 as part of the opening mechanism 7 depends on the number of electromagnets 100. In practice, as many integral housings 300 as electromagnets 100 are provided.

[0094] Orthogonal reference frames X300, Y300, and Z300 are associated with each integral shell 300 and are defined by the longitudinal axis X300, transverse axis Y300, and depth axis Z300 of the integral shell 300, respectively.

[0095] Each integral housing 300 includes Figure 10The upper part of the housing half 302 is visible in its entirety, and the housing half defines a portion 304 for receiving a selection device 400 formed by an electromagnet 100 and two associated retaining rods 200, and a guide portion 306 for two movable hooks 13 intended to be selected by means of the selection device.

[0096] The integral housing 300 shown in the figure has an electromagnet 100 including two pairs of first and second pole surfaces, and two retaining rods 200 arranged along the axis Y100 on both sides of the electromagnet for weaving a two-position jacquard opening mechanism for so-called "flat" fabrics.

[0097] exist Figure 10 The lower right portion shows the receiving portion 304 at a larger scale, while... Figure 10 The lower left portion shows a part of the cover 308 corresponding to part 304. The housing half 302 and the cover 308 together form the integral housing 300.

[0098] The bottom 303 of the housing half 302, parallel to axes X300 and Y300, has longitudinal grooves 310 for guiding the movement of the blades 504 belonging to the movable hook 13. The bottom also has pierced holes 312 for rods or screws to pass through for engaging multiple stacked housings 300 belonging to the integral housing of the opening mechanism 7, which together form all or part of the housing 10.

[0099] In this section 304, the overall housing 300 defines a recess 314 that extends through the bottom 303 and defines a space for partially receiving the electromagnet 100, and two areas 316 for receiving two retaining rods 200 associated with the electromagnet 100.

[0100] The bottom 303 of the housing half 302 is traversed from one side to the other by a circular centering housing 320 along the direction of axis Z300, and is designed to accommodate the centering pin 146 in the mounting configuration of the electromagnet 100 in the overall housing 300. The centering housing has a geometry that is complementary to the geometry of the centering pin 146.

[0101] A centering pin 322 protrudes from the bottom 303 parallel to the axis Z300 and is located between the groove 314 and the guide portion 306 along the axis X300. The centering pin 322 is located opposite the groove 314 to the centering housing 320. The centering pin is intended to engage in the centering recess 126 of the ferromagnetic core 102 in the mounting configuration of the electromagnet 100 in the integral housing 300.

[0102] The overall housing 300 also forms baffles 324 in each region 316 for receiving the retaining rod 200.

[0103] On both sides of the centering housing 320 along the transverse Y300, an integral housing 300 defines housing 326, which is part of a cylinder with a circular cross-section for accommodating the flange 142 of the electromagnet 100. Each housing 326 is defined by an annular surface 328 and a rib 330, the inner surface of which is cylindrical with a circular cross-section and complementary to the outer peripheral surface S'142 of the flange 142 of the electromagnet 100.

[0104] Cover 308 (its surface is in) Figure 10 (See image) is a bottom cover 303, typically facing the housing half 302, defining holes 332 for rods or screws to pass through, which 332 align with holes 312 in the mounting configuration of the top cover 308 on the housing half 302. The cover 308 also defines a centering recess 334, which aligns with a centering recess 320 in the mounting configuration of the top cover 308 on the housing half 302. Alternatively, the cover 308 may not include the centering recess 334. The cover 308 further defines two recessed housings 336, each formed by an annular plane 338 and a rib 339. These recessed housings 336 are respectively aligned with one of the housings 326 in the mounting configuration of the cover 308 on the housing half 302.

[0105] Components 302 and 308 are manufactured by injection molding of an electrically insulating polymeric material, which may optionally be reinforced with fibers to improve its mechanical properties. Components 302 and 308 are non-magnetic.

[0106] In the mounting configuration of the retaining rod 200 on the electromagnet 100, the first longitudinal end 206 of the metal armature 202 is mounted around a guide shaft 144. For this purpose, axes A144 and A210 coincide, surfaces S144 and S210 are radially oriented toward axis A144, and the corresponding dimensions of surfaces S144 and S210 are selected to allow each retaining rod 200 to pivot about the pivot axis X144 while effectively guiding this pivoting movement.

[0107] In the mounting configuration of the selection device 400, the orthogonal reference frames X100, Y100, Z100 and each of the orthogonal reference frames X200, Y200, Z200 are substantially coincident, and the amount of swing of the retaining rod 200 about the axis A144 of the guide shaft on which it is mounted is ignored.

[0108] In the mounting configuration of the selection device 400 within the integral housing 300, each retaining rod 200 extends downward from its first end 206 generally along the longitudinal direction of the integral housing 300 (i.e., parallel to axis X300). In this configuration, orthogonal reference frames X100, Y100, Z100, X200, Y200, Z200 and X300, Y300, Z300 substantially coincide.

[0109] exist Figure 11 In the mounting configuration shown below, the outer attraction surface S208 of each retaining rod 200 faces one of the lower pole surfaces S124 of the electromagnet 100 parallel to the axis Y100, but does not contact that lower pole surface.

[0110] Each retaining rod 200 is mounted about axis A144 of guide shaft 144, around which a first longitudinal end 206 of armature 202 is mounted. The retaining rod moves between a position in contact with an electromagnet (in this example, in contact with the lower branch 124 of ferromagnetic core 102) and a position away from the electromagnet, wherein a void E of non-zero dimensions along axes X100, Y100, and Z100 exists between the electromagnet (lower branch 124 in this example) and the rod 200. Specifically, at the position away from the electromagnet 100, the depth of the void E, measured along the Y-axis, is non-zero. In practice, the terms "away from" and "in contact with" used to define the position of the retaining rod relative to the electromagnet refer to the nature of its distance from or contact with the abutment surface S204 of the electromagnet. Figure 11 The retaining rod 200 shown at the bottom is in contact with the electromagnet, and Figure 11 The rod 200 shown at the top is located away from the electromagnet.

[0111] In the configuration of the rod 200 in contact with the electromagnet 100, surface S204 contacts the lower pole surface S124 to limit Figure 11 The pivoting movement of the rod 200 shown in the lower middle part is in the triangular direction around the axis A144 of the guide shaft 144, in which the rod 200 is pivotally mounted on the guide shaft 144.

[0112] In this contact position, the outer attraction surface S208 does not contact the lower pole surface 124, but is separated from it by a distance because there is a non-zero lateral gap J1 between surfaces S208 and S124. The size of the gap J1 is measured parallel to axes Y100, Y200, and Y300. The presence of a non-zero gap J1 along the entire length of surface S208 along axis X100 and along the entire thickness of surface S208 along axes Z100, Z200, and Z300 means that there is an air gap between surfaces S124 and S208. This air gap exists between the armature 202 and the pole surface S124. In other words, when in the contact position of the rod 200, there is no contact between the armature 202 and the lower branch 124 of the ferromagnetic core 102. Specifically, in the contact position of the rod 200, there is no contact between the armature 202 and the second lower pole surface S124. This is due to the fact that the abutment surface S204 on the retaining rod 200 protrudes relative to the external attraction surface S208 along the direction of the electromagnet 100. In other words, in the mounting configuration of the retaining rod 200, the abutment surface S204 protrudes laterally relative to the external attraction surface S208 in a direction parallel to the Y200 axis and facing the electromagnet, and when the rod 200 pivots from a position away from the electromagnet to a position in contact with the electromagnet, the abutment surface S204 contacts the second pole surface S124, keeping the external attraction surface S208 at a distance from the second pole surface S124.

[0113] Surface S208 is an external attraction surface, wherein when the rod 200 is in contact with the electromagnet 100, and when the electromagnet is activated, the magnetic attraction between the ferromagnetic core 102 and the metal armature 202 is applied through surface S208.

[0114] exist Figure 9 It is noted that armature 202, particularly portion 208A of end 208, does not extend longitudinally through the entire abutment surface S204.

[0115] The external attraction surface S208 is arranged longitudinally relative to the retaining rod 200, specifically along axis X200 between the abutment surface S204 and axis A210. The length l8 of the external attraction surface S208 is greater than the length l4 of the abutment surface S204, which faces the lower pole surface S124 at the contact position of the retaining rod 200 and forms a contact area between surfaces S204 and S124. Lengths l4 and l8 are measured parallel to axis X200. Figures 1 to 15In the illustrated embodiment, the entire abutting surface S204 faces the lower pole surface S124 at the contact position of the retaining rod 200. However, it is conceivable that only a portion of this surface S204 contacts or faces the lower pole surface S124. In this case, the length l4 of this portion of surface S204 that contacts the pole surface S124 also forms the contact area between surfaces S204 and S124, which is chosen to be less than the length l8.

[0116] Note the length of l48 measured parallel to axis X200. The metal armature 202 of retaining rod 200 extends beyond the length measured parallel to axis X200 from end 206. Figure 8 A line L1 within the plane defines the boundary between surfaces S208 and S204. This line L1 is perpendicular to... Figure 12 The plane, and Figure 8 The connection area Z1 between components 202 and 204 is visible on the surface of the retaining rod 200. Therefore, the length l48 corresponds to the overlap length between the second longitudinal end 208 and the abutment surface S204. The ratio l48 / l4 is less than 0.2. In other words, the abutment surface S204 overlaps with the armature 202 by less than one-fifth of the useful portion length l4 of the abutment surface S204 used to secure the armature to the electromagnet. This results in the portion of the non-magnetic body 204 constituting the abutment surface S204, the selection nose 216, the guide ramp 218, and the pin 220 forming the lower end of the retaining rod 200, which has essentially no metal armature below the outer attraction surface.

[0117] In the mounting configuration of the selector 200 within the integral housing 300, deflectors 226, 228, and 230 engage in receiving areas Z226, Z228, and Z230 formed by baffles 324. Therefore, the engagement of the deflectors and baffles isolates certain internal portions of the integral housing 300, equipped with the selector 400, from the guide portion 306, thereby protecting these portions from the accumulation of dust, sludge, or grease.

[0118] In the mounting configuration of the selection device 400 within the overall housing 300, a compression coil spring 340 is inserted between the central rib 342 of the housing 300 and the non-magnetic body 204 of the retaining rod 200. By default, each spring 340 has the function of returning the retaining rod 200 it pushes to a position away from the electromagnet 100. On one side of the non-magnetic body, a pin 220 engages inside the spring 340, allowing the spring to be centered, while a ring portion 222 allows the terminal coil of the spring to be accommodated around the supporting pin 220. When the ring portion 222 surrounds the entire periphery of the pin 220, the end coil of the spring 340 must rest against the ring portion 222 without the risk of the end coil slipping on the pin 220 side, which ensures the repeatability of the spring 340's rebound force.

[0119] Each movable hook 13 includes a body 502 made of plastic material and a flexible blade 504 mounted on the body 502. The flexible blade, preferably metal, is designed to slide against a guide ramp 218 of the retaining rod 200 and includes an opening 508 in… Figure 11 As shown by the dotted line and known in itself, the selector nose 216 of the retaining rod 200 can engage into this opening. Here, the features of the movable hook described in EP-A-1852531 or EP-A-1413657 can be used.

[0120] In the lower part, each body 502 is overmolded onto the end of the thread 12 supporting the lip and nose portion 11. Each body 502 defines a support bracket 506 on the blade portion 14. For this purpose, each support bracket 506 protrudes laterally from the integral housing 300, wherein a movable hook 13 is positioned in a shape-matching manner on the upper surface of the blade portion.

[0121] exist Figures 11 to 15 In the mounting configuration, the first longitudinal end 206 is partially accommodated in space V1. For example, in... Figure 13 As can be seen more specifically, surface portion S206A is located opposite the first pole face S122 formed by the ferromagnetic core 102. These opposing surfaces are in the form of a portion of a cylinder with a circular base centered on axes A122, A144, and A210, and then merged. These surfaces define a gap J2 between them, which is radially spaced from axes A122, A144, and A210. This radial gap J2 has a non-zero width, which is measured radially along axes A122, A144, and A210. This radial gap J2 defines an air gap between surfaces S122 and S206A. In practice, the radial width of the air gap defined by gap J2 can be between 0.1 and 0.2 millimeters (mm), preferably on the order of 0.15 mm.

[0122] P144 is a transverse plane that is parallel to axes Y100, Y200 and Y300 on one hand, parallel to axes Z100, Z200 and Z300 on the other hand, and perpendicular to axes X100, X200 and X300, and contains axes A122, A144 and A210.

[0123] The air gap defined by the radial gap J2 extends about axis A122 over the entire angular sector at vertex α. A first portion of this entire angular sector lies below the transverse plane P144, on one side of the second pole face S124 relative to this plane, and has an angle at vertex α1. A second portion of this entire angular sector lies above the transverse plane P144, i.e., opposite to the second pole face S124, and has an angle at vertex α2. The sum of angles α1 and α2 equals angle α. Angles α, α1, and α2 represent the angular magnitudes of the entire angular sector and its first and second portions, respectively. In other words, each first pole face S122 of the electromagnet 100 extends on both sides of the transverse plane P144 and includes a first portion S122A located on the same side of the plane as the second pole face S124 and having an angular amplitude α1, and a second portion S122B located on the opposite side of the plane as the second pole face S124 and having an angular amplitude α2.

[0124] The ratio α1 / α is between 0.2 and 0.4, preferably equal to 0.33. In this preferred case, the ratio α1 / α2 is 0.5.

[0125] The good geometric accuracy achieved at the air gap defined between surfaces S122 and S206A allows for optimization of the dimensions of these surfaces. Specifically, the ratio between the diameter of surface S122 and the diameter of surface S144 can be selected to be greater than 1.4, preferably on the order of 1.5. This good accuracy also allows the first and second pole faces S122 and S124 to be spaced apart along a longitudinal direction parallel to axis X100 or axis X300 without affecting the longitudinal dimensions of the electromagnet. This results in a relatively small amplitude of the angular pivoting motion of the retaining rod 200 about the oscillation axis A144 between the far-off position and the contact position, such that the air gap at the lower pole face S124 has a width measured along axes Y100, Y200, Y300, which varies little along the length of the outer attraction surface S208. This good accuracy further allows for a reduction in the outer diameter of the guide shaft 144, thereby reducing the external dimensions of the first longitudinal end 206 and thus reducing metal loss during the manufacture of the metal armature 202.

[0126] During the manufacture of the opening mechanism 7, the frame 104 is overmolded onto the ferromagnetic core 102, followed by the installation of the windings 106, contacts 110, and connecting wires between these contacts and the windings 106, and then the overmolded cover 108 is applied. The electromagnet 100 and its guide shaft 144 thus manufactured are inserted into and secured in the housing half 302 of the integral housing 300. The electromagnet 100 is inserted into the centering groove 314 in a direction parallel to the axis Z300 by inserting the centering pin 146 into the centering groove 320 of the integral housing 300. The centering pin 146 is located between and equidistant from the two upper pole faces S122, and its installation in the bottom 303 of the housing half 302 of the integral housing 300 allows for positioning of the electromagnet 100 within the integral housing 300 in the longitudinal and transverse directions parallel to the axes X300 and Y300, respectively.

[0127] Furthermore, the centering notch 126 of the ferromagnetic core 102 is positioned without gap in the transverse direction parallel to the axis Y300 around the centering pin 322 of the complementary shape located on the housing half 302.

[0128] Then, the winding 106 of the electromagnet 100 is aligned with the groove 314 provided at the bottom of the housing, which is parallel to the axis Z100.

[0129] Then, the frame 104 of the electromagnet 100 is supported on two support surfaces of the bottom 303 of the housing half 302, one between the lower pole surface S124 and the other between the upper pole surface S122.

[0130] The outer peripheral surface S'142 of flange 142 is the radially outer surface of a cylindrical portion centered on shaft 144, which subsequently coincides with axis A122. During the mounting of electromagnet 100 in integral housing 300, each flange 142 of electromagnet 100 engages in housing 326 of integral housing 300, as... Figure 14 and 15 As shown. Then, the radial outer surface S'142 of flange 142 is... Figure 15 In the plane, the corresponding rib 330 faces along the longitudinal directions parallel to the vertically downward axes X100, X200, and X300. Therefore, a portion of the rib 330 is arranged opposite to surface S'142 along the longitudinal direction. Figure 15 Within the plane of the plane, a reduced longitudinal gap J3 is defined between the outer peripheral surface S'142 and the rib 330. Therefore, when the electromagnet 100 is placed within the integral housing 300, this gap J3 is vertical and, in practice, has a non-zero width to prevent the placement from resulting in a hyperstatic condition. The width of the gap J3 is measured parallel to the axis X300. The width of the gap J3 is less than or equal to 0.5 mm.

[0131] After the electromagnet 100 is installed in the housing half 302 and in the operating configuration of the mechanism 7, the swing axis A144 is fixed relative to the housing half 302 and the electromagnet 100. The free end 144E of the guide shaft 144 extends from the bottom 303 of the housing half 302. In other words, the two guide shafts 144 extend with their axis A144 parallel to the axis Z300 and perpendicular to the bottom 303 of the housing half.

[0132] Then, the retaining rods 200 are positioned around the guide shaft 144 of the frame 104 by positioning the first longitudinal end 206 of each retaining rod 200 around the guide shaft 144. For this purpose, the axis A210 of each retaining rod 200 is aligned with axes A122 and A144, and then the first longitudinal end 206 of the armature 202 is partially engaged in the space V1 by axial translation parallel to axes A122, A144 and A210 until it abuts against the surface S142 of one of the flanges 142. This is equivalent to hooking the retaining rod onto the electromagnet in the integral housing. The orientation of the retaining rod is chosen such that a portion S206A of the outer surface S206 of each first longitudinal end 206 then faces the upper pole surface S122. On the other hand, due to this arrangement, each outer attraction surface S208 faces the lower pole surface S124 of the electromagnet 100 along a transverse direction parallel to axes Y100, Y200 and Y300.

[0133] Since the first pole face S122 and the second pole face S124 are offset and spaced apart along the longitudinal direction, the longitudinal portion of the metal armature 202 of each retaining rod 200 does not face the first pole face S122 or the second pole face S124, but is located longitudinally at the height of the center rod 120 of the core 102 and the winding 106.

[0134] When the retaining rod 200 is installed in the integral housing 300 equipped with an electromagnet, during the aforementioned axial translation, the deflectors 226, 228 and 230 of the non-magnetic body 204 engage in the regions Z226, Z228 and Z230 defined by the baffle 324.

[0135] After the two retaining rods 200 are mounted on the electromagnet 100, these retaining rods are connected to the rest of the selection device 400, and since the electromagnet 100 is fixed in the integral housing 300, each retaining rod can rotate about an axis A144 fixed relative to the integral housing 300.

[0136] Therefore, the outer radial surface S144 of the guide shaft 144 forms a cylindrical guide surface that cooperates with the retaining rod 200 during pivoting motion about its swing axis A144, and more specifically, with the surface S210 of the housing 210, reducing the clearance. The reduced clearance refers to the radial clearance at the swing axis A144, which is strictly smaller than the clearance J2, ensuring a non-zero air gap between the surface S206 and the adjacent first pole face S122, thus preventing contact between the armature 202 of the rod 200 and the pole face S122, both in the remote position and the position in contact with the retaining rod. The guide surface S144 is formed on the non-magnetic portion of the electromagnet. Each guide shaft 144 forms an attachment point from the rod 200 to the housing 300, which is fixed relative to the electromagnet 100.

[0137] The deflectors 226 and 228, in conjunction with the regions Z226 and Z228 defined by the baffle 324, isolate a region of the housing containing the first longitudinal end 206 of the armature 202 of each rod and the associated guide shaft 144. This region is dedicated to the hinge of the rod 200 to the electromagnet 100. This allows for the lubrication of the pivoting link formed between surfaces S144 and S210, which can be lubricated.

[0138] The cooperation of deflectors 228 and 230 with areas Z228 and Z230 defined by baffle 324 also enables the isolation of the attraction area defined between the lower pole surface S124 on one hand and the outer attraction surface S208 and the abutment surface S204 on the other. This keeps the attraction area free of grease and dust, ensuring a satisfactory air gap between the lower pole surface S124 and the outer attraction surface S208 when the retaining rod 200 is in its contact position with the electromagnet.

[0139] Then, the two retaining rods 200 can then revolve around their respective guide shafts 144. Figure 11 The top and bottom of the device are shown swinging between the away and contact positions, respectively. In a manner known per se, this allows the movable hook 13 to be selectively held in place based on commands from the electrical contact 110 to the electromagnet 100.

[0140] The movable hook 13 and the cord 12 can then be positioned in the guide portion 306 of the housing half 302. Alternatively, the movable hook 13 and the cord 12 can be placed in the housing half preceding the elements 100 and 200.

[0141] After the retaining rod 200 is placed on the electromagnet 100 (the electromagnet itself is located within the integral housing 300), the free end 144E of the guide shaft 144 protrudes from the retaining rod 200 along a direction parallel to axes Z100, Z200, and Z300. Then, by aligning the hole 332 with the hole 312 and aligning the housing 336 with the free end 144E of the guide shaft 144, the housing half 302 can be covered by the cover 308, thus the housing half 302 and the cover 308 are stacked along axis Z300. A connecting rod or screw is then placed in holes 312 and 332.

[0142] Alternatively, each housing half 302 equipped with the selection device 400 can be stacked, with the bottom 303 of one housing half serving as a cover for the adjacent housing half, and the cover 308 used only for the last housing half 302. Figure 14 and Figure 15 This configuration is partially shown. In this case, the holes 312 of the housing half 302 are overlapped, and then connecting rods or screws are placed in these holes.

[0143] Consider an electromagnet 100 installed in a first housing half 302, which is part of a first integral housing 300. In this case, the free end 144E of the electromagnet's guide shaft 144 engages in a housing 344 of a corresponding shape disposed on the bottom surface 303 of a second adjacent housing half 302, which covers the first housing half 302 by stacking two housing halves 302 along the axis Z300. The housing 344 is used here in place of the housing 336 of the cover 308. The first integral housing is formed by the bottom 303 of the first and second housing halves. This is also true for the other integral housings, except that the last housing is covered by the cover 308. A concave housing 344 is arranged on the side of the bottom 303 of the second housing half 302 opposite to the electromagnet 100 contained within that housing half. The bottom 346 of the concave housing 344 of the second housing half contacts the free end 144E of the guide shaft 144 in a direction parallel to the axis Z300. Furthermore, the cylindrical wall 348 defining the housing 344 is substantially complementary to the outer peripheral surface S144 of the guide shaft 144, thereby centered each guide shaft in the second housing half 302 of the second integral housing 300.

[0144] Figure 14 and Figure 15 As shown, the bottom of the first housing half of the stacked unit housing is not provided with a recessed housing 344, which is unnecessary.

[0145] On the other hand, a flange 142 of the electromagnet housed in the first housing half is formed by the bottom 303 of the second housing half 302 and surrounds the flat annular surface 338 of the concave housing 344. The first end 206 of the armature 202 is located between the surfaces S142 and 338, which face each other along a direction parallel to the axis Z300. In other words, the surface 338 serves as a cover for the space V1 that partially houses the armature 202.

[0146] If cover 308 is used, the flat annular surface 338 of the concave shell 336 encloses the space V1.

[0147] exist Figure 14 and 15 In the stacked configuration shown, the housings 300 are centered relative to each other in the longitudinal and transverse directions parallel to axes X300 and Y300, and are in contact with each other in the direction of axis Z300.

[0148] In operation, each electromagnet 100 selectively controls the holding or releasing of either of two movable hooks 13 located on either side of the electromagnet, arranged within the same integral housing 300, by means of its associated two retaining rods 200. Figure 11 The image shows two movable hooks 13 near the dead point of their trajectory. The selection nose 216 of the retaining rod is inserted into the hole 508 of the blade 504 of the movable hook. Figure 11 The upper part of the movable hook 13 is visible and hooked onto the corresponding retaining rod 200, which is possible because the retaining rod 200 is located away from the electromagnet 100. Figure 11 The lower part of the movable hook 13 is moved away from the selection nose 216 of the corresponding retaining rod held in the contact position, so that the selection nose 216 is not in the path of the upper end of the blade 504 of the movable hook.

[0149] Near the top dead center of its trajectory, the blade 504 of each movable hook 13 contacts the guide ramp 218 of the corresponding retaining rod 200 and counteracts the force exerted by the spring 340 engaged around the pin 220 of the retaining rod, applying a lateral force parallel to the axis Y100 and pointing towards the electromagnet on the retaining rod. This lateral force causes the retaining rod to move away from its position (e.g., around its swing axis A144) from its position away from the electromagnet. Figure 11 (As shown in the upper part) pivot to its contact position (as shown in the upper part) Figure 11 (As shown in the lower part). This operation constitutes the leveling of the retaining rod 200.

[0150] During the displacement of each retaining rod 200, the upper air gap defined by the radial gap J2 remains the same, having a non-zero value, between its position away from the electromagnet 100 and its position in contact with the electromagnet. During this displacement, the lower air gap defined between the outer attraction surface S208 and the lower pole surface S124 decreases until it has a non-zero width, such as... Figure 12 The gap J1 is shown in the figure. Due to the fact that both surfaces S204 and S208 are supported by the retaining rod 200 and the contact between the abutting surface S204 and the electromagnet, especially at the level of its lower pole surface S124, the non-zero value of the lower air gap is well controlled, which is arranged opposite to the external attraction surface S208.

[0151] The value of gap J1 is chosen as a function of the magnetic force applied to the retaining rod 200 to keep it in contact with the electromagnet 100. This depends on the magnetic properties of the armature 202 and the stiffness constant of the spring 340. In practice, the value of gap J1 is between 0.01 and 0.06 mm, preferably between 0.025 and 0.05 mm, and more preferably around 0.04 mm.

[0152] When the retaining rod is in the contact position, the electromagnet 100 is energized, and a magnetic attraction is applied between surfaces S124 and S208. The magnetic circuit passing through the upper and lower air gaps and through the metal armature 206 of the retaining rod 200 counteracts the spring force applied by the spring 340, holding the rod in contact with the lower pole surface S124. In this case, the nose 216 of the retaining rod 200 does not interfere with the downward movement of the blade 504 of the movable hook 13, which follows the downward movement of the blade 14. Conversely, if the electromagnet is not energized when the retaining rod is in its contact position with the electromagnet, the retaining rod does not remain in contact with the electromagnet, and under the action of the spring force applied by the spring 340, the retaining rod pivots away from the lower pole surface S124 as the movable hook descends with the blade. In this case, although the blade 14 moves downward, the selection nose 216 engages in the hole 508 provided in the blade 504 so as to hold the movable hook 13 in an upper position near the top dead center of its trajectory through its surface S216.

[0153] Therefore, the metal armature 202 of each retaining rod 200 is configured to interact with the pole faces S122 and S124 of the electromagnet 100 according to the activation of the electromagnet, so as to control the angular position of the retaining rod relative to the electromagnet about its swing axis A144. This allows the movable hook 13 stopped on the blade 14 to be selected (i.e., held in the upper position) or released (i.e., lowered) when the blade 14 begins to move downward. Specifically, the electromagnet 100 is used to control whether the retaining rod 200 is held in the position of contact with the electromagnet.

[0154] If the movable hook 13 is already held by the holding rod 200, when the corresponding blade 14 reaches the vicinity of the top dead center position of its trajectory again, the blade 14 pushes the body 502 and blade 504 of the movable hook upward again, and the blade abuts against the guide ramp 218 again, so that the holding rod remains in contact with the lower pole surface S124 of the electromagnet 100 as part of the leveling. As mentioned above, depending on the activation of the electromagnet 100, the movable hook 13 may or may not remain in contact with the electromagnet.

[0155] Alternatively, a movable hook ensures that the retaining rod moves from its remote position to its contact position without keeping the retaining rod in contact with the electromagnet, the remaining travel of the retaining rod to its contact position being caused by the activation (“call”) of the electromagnet.

[0156] In the first embodiment, a single abutment surface S204, located as far away as possible from the swing axis A144 of the retaining rod 200, is used, thereby reducing the length of the metal armature 202 to the minimum length required to establish a magnetic circuit between the first and second pole faces. Specifically, the metal armature may extend only to the junction between the abutment surface S204 and the external attraction surface S208, marked by line L1. This reduces the length of the armature 202, thereby reducing the inertia of the retaining rod 200 and its cost.

[0157] exist Figure 16 In the second to fifth embodiments shown, elements similar to those in the first embodiment have the same references and operate in the same manner. The differences between these embodiments and the first embodiment are mainly described below. References used for portions of the second to fifth embodiments that are not visible in the corresponding figures should be understood to refer to portions of the same references in the first embodiment.

[0158] exist Figure 16 In the second embodiment shown, the retaining rod 200 carries an abutment surface S204, which is located along the axis X200 between two portions S208A and S208B of the external attraction surface S208. Therefore, the external attraction surface S208 moves on both sides of the abutment surface S204 along a longitudinal direction parallel to the axis X200.

[0159] At the contact position of rod 200, there is a non-zero air gap J1 between each of the two parts S208A and S208B and the adjacent lower pole surface S124. In other words, at the contact position, the outer attraction surface S208 is a distance away from the second pole surface S124.

[0160] exist Figure 17In the third embodiment shown, along a longitudinal direction parallel to axis X200, the abutment surface S204 is located between axis A210 and the external attraction surface S208. In other words, the abutment surface S204 is located above the external attraction surface S208 within the opening mechanism 7 in the mounting configuration, while... Figures 1 to 15 In the embodiment, it is located below.

[0161] Depend on Figure 18 and 19 In the fourth embodiment shown, the first pole face S122 formed by the ferromagnetic core 102 of the electromagnet 100 is located at the lower transverse branch 122 of the ferromagnetic core 102 in the lower part of the electromagnet 100, while the second pole face S124 is located at the upper transverse branch 124 of the ferromagnetic core 102 in the middle part of the electromagnet 100. In the operating configuration of the opening mechanism to which the electromagnet 100 belongs, the second pole face S124 is arranged above the first pole face S122 along the longitudinal direction of the electromagnet 100 parallel to the axis X100. The frame 104 of the electromagnet 100 has two positioning grooves 145 for receiving positioning members disposed in the body 300 of the opening mechanism. The second pole face S124 has a notch and a transverse groove 125 that extends parallel to the axis Z100 and defines individual strips of material between them in a manner similar to the grooves 224 and strips formed on the surface S204 of the first embodiment.

[0162] Here, along the longitudinal direction parallel to the axis X200, two abutting surfaces S204 are defined on the retaining rod 200 on both sides of the outer attraction surface S208 defined by the armature 202 of the rod.

[0163] Furthermore, a portion 206 of the armature 200 (whose opening 210 engages around the guide shaft 144) is defined in the middle region of the rod 200. In other words, in addition to this portion 206, the armature 202 also includes two branches 205 and 207, which extend from this portion 206 in opposite longitudinal directions, generally parallel to the axis X200, and respectively carry the first portion 204A and the second portion 204B of the nonmagnetic body 204 of the retaining rod 200.

[0164] Part 204A defines the nose 216 and the guide ramp 218. Part 204B defines two abutment surfaces S204. As in the previous embodiment, by default, the spring 340 tends to remove the abutment surfaces S204 from the electromagnet 100.

[0165] like Figure 19As can be seen, when the retaining rod 200 contacts the electromagnet 100, one of these abutting surfaces S204, namely the abutting surface closest to the swing axis A144, abuts against the second pole surface S124, while the second abutting surface S204 furthest from the swing axis A144 abuts against the surface S104 defined by the frame 104. For simplicity, this surface S104 is only shown in... Figure 18 On the right side, a portion of electromagnet 100 is omitted.

[0166] In this fourth embodiment, since portions 204A and 204B of the nonmagnetic body 204 are not integral with each other, portion 204A can be omitted. In this case, the selector nose and retaining ramp are formed directly on the armature 202 and can engage with a molded hook of synthetic material, as envisioned in EP-A-0823501.

[0167] In the Figure 20 In the fifth embodiment shown, only half of mechanism 7 is shown for simplicity. As envisioned in EP-A-1413657, EP-A-0823501, or EP-A-0577524, each guide shaft 144 is arranged on the integral housing 300, the guide shaft 144 being integral with the integral housing 300 and protruding from the bottom 303 of the electromagnet 100 housing half 302. There is no flange 142. After the electromagnet 100 is mounted in the half housing 302 and in the operating configuration of mechanism 7, the swing axis A144 is fixed relative to the half housing 302 and the electromagnet 100. The portion 206 of the armature 202 hinged to the guide shaft is the middle portion of the armature 206, and the armature 202 includes two branches 205 and 207, which extend from the portion 206 in two opposite directions along the longitudinal direction. This is common to the previous embodiments.

[0168] Here, the non-magnetic body 204 defines a guide ramp 218 and a through hole 216 on one side of the branch 205. The through hole is defined on the longitudinal side of the ramp 218 by a surface S216 for hooking the nose 506 of the movable hook 513. The non-magnetic body 204 defines an abutment surface S204 opposite to the ramp 218 relative to the portion 206. This abutment surface abuts against the external attraction surface S208 defined by the end 208 of the branch 207, and this abutment surface faces the second pole surface S124.

[0169] Here, the guide ramp 218 and the selection surface S216 are integrated with the abutment surface S204.

[0170] exist Figures 16 to 20 In one embodiment, in the contact configuration of the retaining rod 200 in contact with the electromagnet 100, there is a non-zero width air gap between surfaces S208 and S124, which is represented as gap J1 in these figures.

[0171] Regardless of the embodiment, the fact that the swing axis of the retaining rod is arranged at the longitudinal height of the first pole face ensures good control of the air gap between the armature of the movable retaining rod and the first pole face. The radial width of the air gap is equal to the non-zero gap J2 radially to axes A122 and A144, regardless of the position of the retaining rod between its remote position and its contact position with the electromagnet. Alternatively, the gap J2 can be variable within the angular range of the air gap between the armature and the first pole face. On the other hand, when the retaining rod is in its contact position with the electromagnet, the abutment surface ensures good control of the air gap, the width of which is equal to the gap J1 between the retaining rod and the second pole face, measured parallel to axes Y100, Y200, and Y300. Because the abutment surface is located on the retaining rod, rather than on the electromagnet, its position relative to the guide ramp and the selection nose is very precise, especially more precise than if the surface were located on the electromagnet. Furthermore, providing an abutment surface on the retaining rod simplifies the structure of the electromagnet, which is a more cumbersome and complex part to manufacture than the retaining rod itself.

[0172] Because the contact surface rests against the second pole surface at the contact position of the retaining rod, the positioning of the external attraction surface is well controlled, which reduces the positioning tolerance gap between surfaces S208 and S124 at the contact position. Therefore, the air gap variation at this height is minimized. This also prevents the non-magnetic frame from extending around the lower and upper legs of the electromagnet's ferromagnetic core, thus simplifying the construction of this electromagnet.

[0173] In the first, second, third, and fifth embodiments, where the abutment surface S204 is integral with the guide ramp 218, this allows for optimal adjustment of the stroke and force applied by the retaining rod to ensure flatness, as the movable hook 13 must abut against it. Furthermore, compared to retaining elements that include flexible blades that deform during leveling, the oscillating characteristics of the retaining rod 200 allow for more effective control of the air gap between the outer attraction surface S208 and the lower pole surface S124.

[0174] The fact that the contact surface or the second electrode surface has a notch prevents the formation of grease clumps on these surfaces, thus ensuring the air gap between the external suction surface and the second electrode surface.

[0175] In addition, the length of the second pole surface portion that mates with the abutment surface can be reduced by selecting the length of the outer attraction surface to be greater than the length of the portion of the abutment surface that abuts with the lower pole surface at the rod contact position (preferably more than twice the length).

[0176] In the first, second, and third embodiments, since the guide ramp and the retaining rod are longitudinally opposite to the attachment point of the abutment surface and the outer attraction surface (which is formed by the first longitudinal end of the retaining rod), it can be ensured that once the retaining rod contacts the electromagnet, the portion of the retaining rod including the outer attraction surface will not be deformed by the force applied by the movable hook at the guide ramp.

[0177] Advantageously, when the retaining rod contacts the electromagnet, the abutting surface of the retaining rod contacts the ferromagnetic core of the electromagnet.

[0178] Regardless of the embodiment, the presence of the groove 314 and the fact that the winding 106 is in direct contact with the sides 120C and 120D of the center rod 120 of the ferromagnetic core 102 provide a good compact form for each integral housing 300 equipped with an electromagnet 100 along a direction parallel to the axis Z300.

[0179] In various embodiments, the offset of the deflectors on each lateral side of the integral housing results in them forming relatively long edges on each lateral side of the retaining rod, which improves the obtained sealing performance.

[0180] In all embodiments, in the mounting configuration of the selection device 400 in the opening mechanism 7, the first pole face S122 is offset relative to the second pole face S124 along the longitudinal direction of the opening mechanism, which is parallel to the subsequently coincident axes X100 and X300. The winding extends longitudinally between the first pole face S122 and the second pole face S124.

[0181] According to a variation of the invention (not shown), for the corresponding arrangement of the geometry of the second pole surface S124 of the electromagnet 100 and / or the nonmagnetic frame 104, the abutment surface S204 may protrude from the outer attraction surface S208 in the direction of the electromagnet, but may be aligned with or deviated from the outer attraction surface in another direction opposite to the electromagnet and along the Y200 axis. At the contact position of the retaining rod, a non-zero air gap is ensured between the outer attraction surface and the second pole surface, and at the contact position of the retaining rod, contact between the electromagnet and the abutment surface is ensured.

[0182] According to a variation of the invention not shown, in the example shown, the stop surface S204 may be adjacent to the external attraction surface S208 in a transverse direction parallel to the Y200 axis, rather than in a longitudinal direction parallel to the X200 axis.

[0183] According to another embodiment of the invention (not shown), the retaining rod 200 may have the shape described in EP-A-0851048 with reference 15, having an abutting surface adjacent to the external attraction surface, the abutting surface being intended to interact with the upper pole surface and / or lower pole surface of the upper electromagnet.

[0184] According to an embodiment of the invention not shown, in the case of a dual-position mechanism combination, such as that described in EP-B-1619279, the coupling of the thread 12 to the heddle 3 can be modified to allow three or four positions of the heddle, thereby allowing the weaving of fabrics other than so-called "flat" fabrics. The selection device then includes two or more movable hooks that are integrated in pairs with the same thread.

[0185] According to another variation of the invention (not shown), a single movable hook 13 or two or more movable hooks may be provided in the housing 30.

[0186] The above-described embodiments and variations can be combined to generate new embodiments of the present invention.

Claims

1. A shedding mechanism (7) for a jacquard loom (M), the shedding mechanism comprising at least one movable hook (13), a cutter (14) causing the movable hook to move along a longitudinal direction (X100, X200, X300) between a bottom dead center position and a top dead center position, the hook being able to be held by a selection device (400) when at or near the top dead center position, the selection device comprising at least: - An electromagnet (100) comprising a ferromagnetic core (102) defining at least one first pole face (S122) and at least one second pole face (S124), the pole faces being offset from each other along the longitudinal direction. - A retaining rod (200) configured to hold the movable hook when the movable hook is at or near its upper dead center position, the retaining rod being mounted to pivot about a swing axis (A144) between a remote position away from the electromagnet and a contact position in contact with the electromagnet, the swing axis being fixed relative to the electromagnet (100) in the operating configuration of the mechanism, the retaining rod comprising: A ferromagnetic armature (202) magnetically interacts with the first and second pole faces (S122, S124) to control the angular position of the retaining rod about the swing axis. This armature includes an outer attraction surface (S208) facing the second pole face (S124) when the retaining rod is in a contact position with the electromagnet. • A non-magnetic body (204), which is integral with the armature, The non-magnetic body (204) of the retaining rod (200) is characterized in that it includes at least one abutting surface (S204), the abutting surface being: - Adjacent to the external attraction surface (S208); - When the retaining rod is in a position away from the electromagnet, it moves away from the electromagnet; and - When the retaining rod is in the contact position with the electromagnet, it is in contact with the electromagnet. Furthermore, when the retaining rod is in the contact position with the electromagnet, the outer attraction surface (S208) is away from the second pole surface (S124).

2. The mechanism according to claim 1, characterized in that, Each contact surface (S204) protrudes relative to the external attraction surface (S208) along the direction of the electromagnet (100).

3. The mechanism according to claim 1, characterized in that, Each contact surface (S204) is arranged relative to the external attraction surface (S208) along the longitudinal direction (X100, X200, X300) and is opposite to the swing axis (A144).

4. The mechanism according to claim 3, characterized in that, The armature (202) extends along the longitudinal direction (X100, X200, X300) and from the swing axis (A144) only to the connection area (L1) between the outer attraction surface (S208) and the abutment surface (S204).

5. The mechanism according to any one of the preceding claims, characterized in that, The non-magnetic body (204) of the retaining rod (200) is a single piece, and the retaining rod includes a selection surface (S216) capable of holding the movable hook (13) at or near the top dead center position and / or a ramp (218) for interacting with the movable hook (13) to move the retaining rod (200) from a remote position away from the electromagnet (100) to a contact position in contact with the electromagnet.

6. The mechanism according to any one of claims 1 to 4, characterized in that, When the retaining rod (200) is in the contact position with the electromagnet (100), the abutting surface (S204) abuts against the second pole surface (S124), wherein the second pole surface is the outer surface of the ferromagnetic core (102) of the electromagnet, the outer surface protruding toward the retaining rod (200) relative to the nonmagnetic frame (104) of the electromagnet.

7. The mechanism according to claim 6, characterized in that, The length (l8) of the outer attraction surface (S208), measured along a direction parallel to the longitudinal direction (X100, X200, X300), is greater than the length (l4) of the abutment surface (S204) facing the second pole surface (S124) when the retaining rod is in the contact position where it contacts the electromagnet (100), the length of the abutment surface being parallel to the length measurement of the attraction surface.

8. The mechanism according to any one of claims 1 to 4, characterized in that, When the retaining rod (200) is in the contact position with the electromagnet (100), the retaining rod (200) does not hold the movable hook (13) in or near the top dead center position.

9. The mechanism according to any one of claims 1 to 4, characterized in that, The electromagnet (100) is attached and fixed in the housing (300) of the mechanism, wherein the non-magnetic portion of the electromagnet integral with the ferromagnetic core includes a guide surface (S144) for guiding the retaining rod (200) to pivot about the swing axis (A144), the guide surface engaging with the retaining rod (200) in a direction radial to the swing axis (A144) between the remote position and the contact position of the retaining rod, and wherein the guide surface is cylindrical, having a circular base, and centered on the swing axis.

10. The mechanism according to any one of claims 1 to 4, characterized in that, The non-magnetic body (204) of the retaining rod (200) includes a pin (220) and a ring portion (222) that surrounds the pin on its entire circumference and is configured to receive and support a helical spring (340) for returning the retaining rod (200) to a position away from the electromagnet.

11. The mechanism according to any one of claims 1 to 4, characterized in that, The swing axis (A144) is located at the same height as the first pole surface (S122) along the longitudinal direction (X100, X200, X300).

12. The mechanism according to any one of claims 1 to 4, characterized in that, The armature (202) of the retaining rod is penetrated by a first housing (210) for receiving a guide shaft (144) for guiding the retaining rod (200) to pivot between a remote position away from the electromagnet (100) and a contact position in contact with the electromagnet, wherein the guide shaft extends along the pivot axis (A144), and wherein the armature includes an outer surface (S206A) facing the first pole face (S122) and has a non-zero gap (J2) between the remote position and the contact position in contact with the electromagnet.

13. The mechanism according to claim 12, characterized in that, The mechanism includes a housing (300), one or more of the movable hooks (13) moving within the housing, and the electromagnet (100) attached and fixed within the housing, wherein the guide shaft (144) for guiding the pivoting of the retaining rod (200) is formed on the housing or on the nonmagnetic frame (104) of the electromagnet.

14. The mechanism according to any one of claims 1 to 4, characterized in that, The ferromagnetic core (102) of the electromagnet (100) includes a middle portion (120), a winding is formed around the middle portion (106), and wherein the first pole face and the second pole face (S122, S124) are arranged on both sides of the middle portion along the longitudinal direction (X100, X200, X300).

15. A jacquard loom (M), characterized in that, It includes the opening mechanism (7) according to any one of the preceding claims.

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