FR2713832A1 - Connector, e.g. for telephone line wires - Google Patents

Abstract

The connector consists of an insulating housing (2) with a fixed inner plate (11) which receives the bared ends (3) of at least two wires (7, 8), and a moving plate (17) which is pressed on top of them by a screw (18). The moving blade is made from a flexible metal, equipped with a retaining edge (25) at one end, while its other end is divided by a number of lengthwise slits into a series of separate fingers (28) which lock the wire ends against the fixed plate when the screw (18) is tightened. The housing (2) is made from a rigid insulating material with high mechanical strength and low susceptibility to moisture, e.g. a plastic such as PVC, polyethylene or polypropylene. Its inner chamber, containing the two plates, is filled with a sealing and protecting substance such as grease or petroleum jelly.

Description

 The present invention relates to a connection pad, suitable for connecting electrical wires constituting two by two subscriber telephone lines, to a distribution strip or to a distribution contactor in particular.

 In the usual solutions for producing such studs, the ends of the wires are joined individually, more often in pairs at least of homologous wires of the same polarity mounted in parallel for example, with a clamp comprising, inside a housing. support or the like, a fixed part and a mobile part, the latter being provided with means of the screw and washer type adapted to clamp this mobile part against the fixed part, by trapping the ends of the wires between them.

 However, if the wires do not have a strictly identical outside diameter, the tightening obtained by such a clamp is not perfect, in particular as regards the wire of smaller section. In addition, the conventional connection pads have a structure such that the opening of the clamp for the introduction of the ends of the conducting wires is not very easy to access and above all offers only a reduced available space, making the passage of wires sometimes difficult.

 The present invention relates to an improved connection pad which overcomes these drawbacks.

 To this end, the stud considered, comprising an insulating box delimiting an internal housing for mounting in this housing a fixed support strip for at least two stripped electrical conductors, engaged in the housing by a side window thereof to be placed against the surface of the support strip and then be locked against it by means of another movable contact strip, subjected to a clamping effect against the fixed strip by a control member carried by the housing and exerting a thrust on the movable lamella, is characterized in that the movable contact lamella is constituted by a flexible metallic piece, having at one end a fixing heel in the internal wall of the housing opposite the fixed lamella and, at the other end, a terminal part comprising parallel slots, delimiting in the movable lamella a plurality of independent fingers, so that, under the effect of the organ e of control applied to the opposite surface of the movable lamella, these fingers clamp the wires against the fixed lamella, independently of one another.

 Under these conditions, the movable lamella which has in its end part such contiguous fingers but separated from each other, determines on the stripped ends of the electrical wires engaged inside the housing through the side window thereof, as much independent contact surfaces, the clamping of the movable lamella on the fixed lamella allowing adaptation of each of these fingers to possibly different diameters of the wires, providing a very greatly improved quality of the electrical connection.

 Preferably, the movable strip is constituted by a flexible metal blade, forming a spring, folded back inside the case and curved on itself substantially in a semicircle to present a general U-shaped section, so that its heel one of its ends is anchored in a groove of the housing made in the housing, practically perpendicular to the side window of the housing, the independent fingers of the terminal part at the opposite end of the strip being applied to the conducting wires. being directed towards this window, to the right of it.

 Advantageously, the housing is made of a rigid and insulating material, having good mechanical strength and reduced sensitivity to humidity, in particular of the kind of a plastic material such as polyvinyl chloride, polyethylene or polypropylene.

 According to a particular embodiment of the invention, the control member consists of a single clamping screw passing through one of the walls of the housing and cooperating with a fixed nut immobilized in this wall, so as to apply its end penetrating into the housing on the uncut front part of the movable lamella, preceding its end part.

 Furthermore, the clamping screw may include an operating head provided with an open transverse groove, so as to allow the screw to be driven in rotation in the nut and the force exerted on the movable lamella to be adjusted.

 In a preferred embodiment of the invention, the fixed metal strip also has a curved profile, extending approximately along a fraction of the circumference, with at one end an anchoring heel in the wall of the housing opposite to that carrying the control member, this strip extending by a rear part in contact with the bottom of the housing opposite the side window.

Advantageously, the rear part of the fixed strip engages in a retaining groove made in the bottom of the housing, the curved profile of the strip extending over approximately 1 / 8th of a circle. As a variant, the fixed strip can have a profile bent over approximately 1/4 of a circle, the rear part of the fixed strip then engaging in a retaining groove formed in the wall of the housing receiving the heel of the movable strip and s 'extending parallel to the receiving groove of this heel.

 According to another particularly useful characteristic, the fixed and movable lamellae both have a rough coating, in their surfaces in contact with the ends of the electrical wires, in particular of the "fishbone" type, so as to increase the quality of contact with these wires, as well as their resistance to tearing out of the housing, the clamping pressure exerted between the slats after introduction of the wires into the side window of the housing inside the housing, causing a penetration of the metal of the lamellae into the surface facing the wires, generally less hard, achieving an effect analogous to that of a cold weld.

 Finally and according to yet another characteristic, the housing can be provided with an axial passage hole, passing through the housing outside the internal housing, for mounting a connecting pin between several identical housings, joined together to form a strip distribution for as many pairs of conductive wires.

 Preferably, each housing has two or more superimposed stages, each stage being provided with a lateral window for access to an internal housing containing a fixed lamella and a movable lamella, the successive stages being shifted in depth from one to the next. , in order to allow free access to the control elements of each of them.

 When the connection pad in question is to be used in an aggressive environment, in particular in a humid and / or corrosive atmosphere, the internal housing of the housing can advantageously be filled with a sealing and protective material, of the kind grease, petroleum gel or the like.

Other characteristics of a connection pad for electrical wires of telephone lines in particular will become more apparent from the following description of several exemplary embodiments, given by way of non-limiting example, with reference to the appended drawings, in which
- Figure 1 is a perspective view of an insulating housing for connection pad according to the invention.

 - Figure 2 is a longitudinal sectional view of the part of the housing and of the stud illustrated in Figure 1.

 - Figure 3 is a perspective view illustrating the mounting of a set of boxes of the kind shown in Figure 1, for the production of a distribution strip.

 - Figure 4 is a top view on a smaller scale of an alternative embodiment of the assembly according to Figure 3.

 - Figure 5 is a perspective view of another variant where the mounting of the studs is carried out in accordance with the provisions of Figure 4.

 - Figure 6 is a perspective view illustrating the profile of a variant of a box of the kind used in the assemblies according to either of Figures 4 and 5, this box being seen this time from the side opposite to that shown in this Figure 5.

 - Figure 7 is a longitudinal sectional view of a part of a housing, similar to that illustrated in the section of Figure 2, but corresponding to an alternative embodiment as regards the mode of immobilization of the fixed strip inside the housing of this box.

 In Figures 1 and 2, the reference 1 designates as a whole a connection pad produced in accordance with the invention, comprising an insulating housing 2, preferably made from a rigid plastic material, suitably molded or machined, in particular in polyvinyl chloride, polyethylene or polypropylene.

 The housing 2 is hollow and has a lower wall 3, an upper wall 4 and facing side walls, respectively 5a and 5b, the front wall 5b towards the outside of the housing being pierced with a side window 6, through which penetrate at least two electrical wires, respectively 7 and 8, of the same polarity and forming part of an installation for distributing telephone lines for subscribers.

 The wires 7 and 8 each comprise a conductive core 9, generally made of a copper alloy or other similar material, and an external protective sheath 9a. These wires, the ends of which have been suitably stripped of their sheath to leave their conductive core free, over a certain length, thus engage the latter in an internal housing 10 of the housing 2 delimited therein by its various walls, the penetration of the core being carried out until the protective sheath is substantially in line with the side window 6, allowing, in a manner well known in the art, a suitable positioning in depth of the wires to be connected, while avoiding overflow of a conductive part thereof outside the connection pad.

 The housing 2 is equipped, inside the housing 10, with a first metal strip 11 or fixed strip, the latter having a running part 12, preferably curved on itself and which in the example shown extends on about a quarter of a circle with, at its end closest to the slot 6, an anchor heel 13 folded at right angles to engage in a groove 14 provided in the bottom wall 3 of the housing in order to immobilize the lamella 11. In this embodiment, the lamella 11 is supported by its posterior extension 15, opposite the heel 13, against the surface of the bottom wall 5a of the housing 10 inside the housing, penetrating in a second groove 16 formed in the upper wall 4, as clearly shown in FIG. 2.

 In accordance with the invention, the fixed strip 11 is provided to cooperate with a movable strip 17, forming a spring, so as to apply an adjustable force on the stripped ends 9 of the wires 7 and 8 in contact with the surface of the strip 11, this under the effect of a control member 18, exerting on the movable lamella 17 an appropriate thrust.

 The control member 18 is advantageously constituted by a screw 19, the thread of which is adapted to cooperate with a nut 20, comprising external ribs 21 allowing it to be immobilized by crimping in particular in the upper wall 4 of the housing, the fixing of the nut in this wall which can of course be produced in any other way without departing from the scope of the present invention, the nut being able to be stamped in the housing during the manufacture thereof or put in place subsequently, by force or by blocking by means of crimped washers (not shown).

 At its upper part, outside the housing 2, the screw 19 comprises an operating head 22, provided with an open transverse groove 23, making it possible to drive the screw in rotation inside the nut 20 in making it more or less enter the housing 10 and thus adjusting the force exerted by this screw on the movable strip 17 to tighten or on the contrary loosen the ends 9 of the wires 7 and 8 with respect to the fixed strip 11 .

 According to the invention, the movable strip 17 has a front part 24, full, the end of which has, like the fixed strip 11, an anchoring heel 25, folded at right angles and engaged in an immobilization groove 26 formed in the upper wall 4 of the housing 2, in line with the front wall 5b thereof, parallel to the aforementioned groove 16.

 The front part 24 of the movable lamella 17 is extended by an end part 27, through which a plurality of parallel slots are produced, extending along the length of the lamella, these slots thus forming a series of independent fingers 28 at the end of the latter.

 In the example considered, the movable lamella 17 is formed by means of a flexible metal blade, forming a spring, and curved on itself, substantially in a semicircle, its end portion 27 with its fingers 28 thus being folded over it. -same, so that these fingers are applied from above on the ends of the wires by exerting an adjustable contact force on the fixed strip 11, following the tightening effect produced by the screw 19 pressing on the movable lamella in its full front part 24.

 Preferably, the strips 11 and 17 are produced using a relatively hard metallic material, made of spring steel or the like, the hardness of this material being in any case greater than that of the copper alloy or the like. wires themselves, so as to allow, during tightening, a slight crushing of the ends pinched between the lamellae. Advantageously, the latter have facing external surfaces having a rough appearance, of the fishbone type, so as to obtain excellent electrical contact with the wires, in particular a slight penetration of these roughnesses into the metal thereof, also improving their resistance to tearing out of the housing.

 The upper wall 4 of the housing 2 finally comprises a slot 29, provided substantially in line with the space which separates the two strips, in order to allow the ends 9 of the wires to be seen through this slot, as shown in FIG. 2, so as to control the correct engagement of these wires and their effective tightening between the two strips.

 Note that, when the considered connection pad is placed in an aggressive medium, in particular in a humid or corrosive atmosphere, the housing 10 of the housing 2 can advantageously be filled with a material which achieves a certain tightness and protection therein. effective of the ends of the conducting wires 7 and 8 kept clamped between the lamellae, such a material possibly being a grease, petroleum gel or the like. In this case, the slot 29 formed in the housing in the upper wall 4 of the latter can be eliminated.

 Figure 3 illustrates a particular shape that can be given to the insulating housing of the connection pad, in particular to form by the assembly of several housings of this kind, a distribution strip, preferably even with several superposed stages.

 In this Figure, there are thus shown three boxes, respectively 2a, 2b, 2c, capable of being suitably attached to each other with interposition each time between them of an insulating plate 30 forming an integral part of each of the boxes respectively or cut to the shape of these boxes. These plates and the associated housings also include an axial transverse passage 31 for mounting a connecting pin 32, the latter comprising a central end piece 33, cooperating at each of its ends with a blocking assembly formed by a screw. 34 and a washer 35.

 Each box 2a, 2b, 2c is also advantageously designed during its manufacture to present two stages, respectively 36 and 37, in which the box has a lateral slot 6 for the introduction of the electrical wires into the corresponding front wall 5b, a control member 18 for clamping the movable strip on the fixed strip inside the housing provided in the housing, as described in relation to FIGS. 1 and 2, and an observation slot 29 making it possible to control the positioning suitable place for the wires and their immobilization.

 Preferably even, each box 2a, 2b, 2c not only comprises two superimposed stages 36 and 37, but as shown in FIG. 3, two other stages 36 'and 37' opposite the first according to the length of the box, the stages 37 and 37 'having a longitudinal development lower than that of stages 36 and 36', so that, at the level of the four elements thus formed in each housing, access to the insertion slot 6 of each stage and to the control member 18 associated therewith, can be produced in a simple and convenient manner without interference or discomfort from one floor to another.

 Figure 4 illustrates a top view of another alternative embodiment, in which the assembly of several individual boxes, here three in number, 2 ′, 2 ″ and 2 ″ ’, is ensured, as above, each of these boxes comprising as in the embodiment illustrated in Figure 3, superimposed stages and offset in depth from one housing to the next.

 However, in this case, the successive stages 38 and 39 are arranged on either side of the housing, 40 at the upper part thereof, so that these are offset in the longitudinal direction of these housings with lateral profiles 41 and 42 in cut sides, so that the control members 18 (and consequently the lateral slots for introducing the ends of the conducting wires 7 and 8), are offset in this direction in order to further facilitate setting in place of these wires from one housing to another and, in each housing, from one floor to another.

 Figure 5 shows in perspective a simplified variant of the embodiment proposed in Figure 4, in which the housings comprise as previously superposed stages again offset from one to the other in the longitudinal direction from one housing to the next , but without arranging their lateral profiles with the abovementioned cut sides, the shifting of the housings being effected by simple mutual interlocking before their immobilization is obtained by the connecting pin 32.

 Figure 6 illustrates seen from the side opposite to that shown in Figure 5, a variant of any of the housings used in the latter, making better appear the offset in the longitudinal direction of the superimposed parts of this housing, allowing their interlocking relative during their assembly.

 In this variant, it is also planned to have inside the movable lamella 17 a metal rod 43 of elongated cylindrical shape, the latter being secured to the insulating plate 30 which closes each of the housings on one of the faces of end of it, as already specified with respect to the variants of Figures 3 and 5 in particular. This metal rod makes it possible to distribute the force of the fingers 28 of the end portion 27 of the strip more evenly over the ends devoid of the protective sheath of the electrical conductors mounted inside each of the housings.

 Also on this variant, the insulating plate 30 is provided with flanges 44, projecting upward, making it possible to protect the heads of the control members 18, once the assemblies of the housings have been carried out, these heads being partially hidden by these parallel edges, from one housing to the next.

 FIG. 7 illustrates another variant of the method of mounting the fixed strip 11 inside the housing 10 of the housing 2, presenting with respect to that shown in FIG. 2 a modification as to the immobilization of this strip vis-à-vis -vis the bottom wall 5a of the housing.

 In this case, in fact, the fixed strip 11 is considerably less curved than in the previous variant and extends approximately over 1 / 8th of a circle. In addition, its posterior extension 15, opposite the heel 13, again engages in a groove 16, but this is provided, no longer in the upper wall 4 of the housing but in its lateral bottom wall 5a , substantially in the middle of the height of the latter.

 A connection pad is thus produced, in particular for telephone line wires leading to a distribution strip or a distribution contactor, of simple design and which provides particularly remarkable operational safety, any variations in diameter of a wire to the wire. 'other being without effect on the quality of the electrical connection made between the fixed strip and the movable strip of each pad.

 The formation in each movable lamella of independent fingers makes it possible to ensure a pressure suitably adjusted on each of the stripped ends of the neighboring wires between which a connection is made, the studs being able to be adapted each time to the average dimensions of these wires, in a very wide range of use.

 The clamping fingers of the movable lamella approximate the shape of the wires, improving the electrical contact and the resistance to tearing with respect to the housing, in particular when the lamellae have a suitable rough surface. The arrangement of these strips in the housing of each housing leaves completely free the full width of these strips, avoiding the discomfort produced between them when the clamping means passes through them.

 The assembly can exhibit excellent resistance to humidity and to electrical overloads, with high insulation resistance.

 Of course, it goes without saying that the invention is not limited to the exemplary embodiments more particularly described above with reference to the accompanying drawings; on the contrary, it embraces all its variants.

Claims (12)

 1 - Connection block, in particular for telephone line wires, comprising an insulating housing (2) delimiting an internal housing (10) for mounting in this housing a fixed support strip (11) for at least two electrical conductors (7, 8) stripped (in 9), engaged in the housing by a side window (6) thereof to be disposed against the surface of the support strip and then be blocked against it by means of another movable contact strip (17), subjected to a clamping effect against the fixed strip by a control member (18) carried by the housing and exerting a thrust on the movable strip, characterized in that the movable contact strip consists of a flexible metal part, having at one end a fixing heel (25) in the internal wall of the housing opposite the fixed lamella and, at the other end, an end part (27) comprising parallel slots, delimiting in the movable lamella e a plurality of independent fingers (28), such that, under the effect of the control member applied to the opposite surface of the movable lamella, these fingers clamp the wires against the fixed lamella, independently of one of the other.  2 - Connection pad according to claim 1, characterized in that the movable strip (17) is constituted by a flexible metal blade, forming a spring, folded inside the housing (2) and bent on itself to present a general U-shaped section, substantially in a semicircle, so that its heel (25) at one of its ends is anchored in a groove (26) of the housing formed in the housing (10), practically perpendicular to the side window (6) of the housing, the independent fingers (28) of the terminal part (27) at the opposite end of the strip being applied to the conducting wires (7, 8) while being directed towards the window, in line with this one.  3 - Connection pad according to one of claims 1 or 2, characterized in that the housing (2) is made of a rigid and insulating material, having good mechanical strength and reduced sensitivity to moisture, especially of the kind of a plastic material such as polyvinyl chloride, polyethylene or polypropylene.  4 - Connection pad according to any one of claims 1 to 3, characterized in that the control member (18) consists of a single clamping screw (19) passing through one of the walls (4) of the housing (2 ) and cooperating with a fixed nut (20) immobilized in this wall, so as to apply its end penetrating into the housing (10) on the front part (24) not cut of the movable lamella (17), preceding its end part ( 27).  5 - connection pad according to claim 4, characterized in that the clamping screw (19) comprises an operating head (22) provided with an open transverse groove (23), so as to allow the driving of the screw rotating in the nut and adjusting the force exerted on the movable lamella (17).  6 - Connection pad according to any one of claims 1 to 5, characterized in that the fixed strip (11), metallic, also has a curved profile extending approximately according to a fraction of circumference, with at one end a heel anchor (13) in the wall (3) of the housing (2) opposite to that (4) carrying the control member (18), this strip extending by a rear part (15) supported on the bottom (5a ) of the housing opposite the side slot (6).  7 - Connection pad according to claim 6, characterized in that the rear part (15) of the fixed strip (11) engages in a retaining groove (16) formed, either in the wall of the housing receiving the heel ( 25) of the movable strip (17) and extending parallel to the groove (26) for receiving this heel, or in a groove provided in the bottom (5a) of the housing.  8 - Connection pad according to any one of claims 1 to 6, characterized in that the fixed (11) and mobile (17) lamellae both have a rough coating, in their surfaces in contact with the ends of electrical wires, in particular of the "fishbone" type.  9 - Connection pad according to any one of claims 1 to 8, characterized in that the housing (2) has, in one of its walls (4), an observation slot (29) from the inside of the housing (10).  10 - Connection pad according to any one of claims 1 to 9, characterized in that the housing (2) is provided with an axial passage hole (31), passing through the housing outside the internal housing (10), for mounting a connecting pin (32) between several identical boxes (2a, 2b, 2c), joined together to form a distribution strip for as many pairs of conductive wires.  11 - Connection pad according to any one of claims 1 to 10, characterized in that each housing (2) has two or more superimposed stages (36, 37), each stage being provided with a side window (6) d access to an internal housing (10) containing a fixed lamella (11) and a movable lamella (17), the successive stages being offset in depth from one to the next, in order to leave free access to the control members ( 18) of each of them.  12 - Connection pad according to any one of claims 1 to 11, characterized in that the internal housing (10) containing the fixed (11) and mobile (17) lamellae, is filled with a sealing material and grease, petroleum gel or similar protection.