FR2739727A1 - Gripping/connection mechanism for auxiliary/main cable - Google Patents

Abstract

The mechanism has a lower channel along which a cable (60) can be placed longitudinally. Above this section there is an electrically conducting gripper section (5) with penetrating teeth (51,50). The auxiliary cable (4) is placed in a channel above the gripper. The upper part of the enclosure has a rotating screw shaft (2) attached to a section (21) which tightens on the auxiliary cable. As the screw rotates the first section penetrating teeth pierce the outer sleeves (41,61) of the main and auxiliary cable, contacting the cable inners and gripping them in place.

Description

Cable clamp device with double insulation perforation, for bypassing a
main cable passing.

 The invention relates to a cable clamp device with double insulation perforation, for bypassing a passing main cable.

 The purpose of this type of device is, on the one hand to secure a main cable, called "passing" with an auxiliary or derivative cable.

 Many cable clamp devices are known. To achieve the perforation of insulation, usually used intermediate parts provided with teeth or spikes, similar organs.

 The following French applications or patents may be cited, without limitation: FR-B-2 126 555 (MARS-ACTEL), FR-A-2 596 209 (VERLANT and BAURAIN), FR-A-2 597 664 ( SOCIETE NILED) and FR-A-2 493 612 (SIMEL).

 However, these devices have drawbacks: their structure is relatively complex, in particular because they require at least two clamping screws or equivalent members. In addition, not all of them allow a double perforation: it is then necessary to prepare one of the cables, by stripping it.

 French patent FR-A-2 191 815 (MARS-ACTEL) describes a device requiring only one clamping screw, but its structure remains complex: several intermediate parts, arranged between the main passing cable and the derived cable, are used and the end of the drop cable must be prepared in advance, stripped and inserted into a conductive metal part.

Finally, the request for certificate of addition FR-A-2 378 371 (MARCH
ACTEL) describes a cable clamp device with double perforation of insulation, using only one screw and of simple structure. However, the double perforation is obtained using a metal strip having teeth made by "punctures" and it is necessary to fold this strip in the shape of an eight so as to wrap it around the two cables. This operation can present difficulties in the field, considering that the main passing cable can be in place and live.

 Finally, it is often necessary, and this last example clearly shows, to guide the various parts to be assembled in a precise manner, in particular the branch cable and to maintain them during the tightening operation.

 The invention aims to meet all the needs which are felt in the main application concerned: simple structure of the cable clamp, double perforation of the insulators, precise guidance of the parts to be assembled and their provisional maintenance before the tightening operation is completed, without presenting the drawbacks of the devices of the known art.

 To do this, the invention provides a cable clamp with one-piece body comprising an opening, which will be called by higher convention, in which the main passing cable can be inserted. The upper part of the cable clamp body is closed by locking nut supporting a clamping screw, the lower part of which is extended by a piston. A spacer, comprising teeth, needles or similar members on two opposite faces, is slid into the middle part of the body of the cable clamp between the main passing cable and the branch cable. It is held between the two interior walls of the cable clamp body. We can then operate the final tightening, which simultaneously leads to the perforation and the electrical continuity of the two cables.

 In a preferred variant, there is provided a shoulder for guiding the spacer which keeps it inside the body of the cable clamp even if the latter is presented "upside down".

 Still in a preferred embodiment, the tightening screw includes a double tightening calibration head, which allows tightening in two stages: "approach" and final tightening by successive ruptures of the head.

 Finally, it is possible advantageously to provide a spring for compensating for the creep over time of the cable insulation, that is to say of the material constituting their sheaths.

 One can also provide, in an additional embodiment of the device according to the invention, not a single clamping screw, but two or more.

 According to this embodiment, in particular if two tightening screws are provided, these screws are advantageously provided with breaking tightening calibration heads, the values of the breaking torques of which are not equal. One of the screws is therefore used for an "approach" to tightening ("low" tightening torque), the other for a final tightening torque ("strong" tightening torque).

 The subject of the invention is therefore a cable clamp device with double insulation perforation, for derivation of a main cable passing through at least one auxiliary cable, the two cables being able to be provided with an insulating sheath, device comprising a body provided with an enclosure open so that it can be positioned on the main passing cable, this pressing on the bottom of the enclosure, device comprising at least one screwing member exerting a pressure force on a assembly comprising, superimposed, the main passing cable, an electrically conductive spacer provided with means for perforating said sheaths and the auxiliary cable, characterized in that said body comprises, on the walls of the enclosure, means for longitudinally guiding the 'spacer, in a direction parallel to said main cable passing, and holding inside said enclosure.

 It can therefore be seen that the cable clamp device according to the invention has numerous advantages: simplicity of structure, guiding and holding of the various parts, simplicity of the operations to be carried out.

The invention will be better understood and other characteristics and advantages will appear on reading the description which follows with reference to the appended figures, and among which:
- Figure 1 illustrates schematically, front view, a cable device according to a first preferred embodiment of the invention;
- Figure 2 schematically illustrates, in perspective view, a cable clamp device according to a second embodiment of the invention;
Figure 1 schematically illustrates a cable clamp device 1 according to a preferred embodiment of the invention.

 It comprises a main body 10, constituting a receptacle having the general shape of a "U". On its part which will be called arbitrarily "upper part" 100, it consists of two parallel and vertical walls (in the representation which is given by FIG. 1). This upper part 100 therefore opens onto the external environment, and naturally the body 10 opens forward and backward. This opening, between the two wings of the "U" allows to thread the body 10 on the main cable 6, said "passing", in any longitudinal position thereof.

 The bottom 102 of the main body 10, the walls of which advantageously form a "V", is then positioned against the sliding main cable 6. The latter usually comprises an insulating sheath 61 and a multi-strand core 60.

 The cable is then held at the bottom of the cable clamp 6, while sliding a conductive spacer 5 provided, on upper and lower faces, with teeth or spikes, with similar members, 50 and 51 respectively. These organs have the function of perforating an insulating cable sheath when they are pressed on it. In a variant, of this spacer (not explicitly shown), instead of being made of conductive material, the body can be made of insulating plastic material. I1 then suffices to provide conductive tips piercing, from side to side, this body and ending on the upper and lower faces. The conductive spacer is guided, inside the body 10 of the cable clamp 1, by the side walls of its central part 100. To do this, the side walls 53 of the spacer 5 are advantageously flat. On the other hand, the upper and lower walls, 54 and 55, provided with teeth, 50 and 51, are curved so as to best match the surfaces of the cables, 4 and 6.

 In an advantageous embodiment, the central part 100 is provided with an upper shoulder 103. This has an additional guiding function which makes it possible to maintain the spacer 5, even if the cable clamp 1 is presented upside down , during its insertion on the main passing cable 6. To do this, the spacer 5 has two upper lateral grooves 52, complementary to the shape of the shoulder 103.

 The following operation consists in threading the branch cable 4 above the spacer, that is to say between the walls of the upper part of the body 10 of the cable clamp 1. The latter usually comprises an insulating sheath 41 and a multi-stranded soul 40.

 Then, this branched cable 4 is maintained for the time required to position a screwing assembly 2 inside the body 10 of the cable clamp 1. To do this, the screwing assembly comprises a proper screw 20 rotating in a block 24 comprising a threaded hole piercing it right through so that the screw acts on a piston 21. The block 24 includes guide grooves 240 on the side walls so as to be able to thread the block 24 on complementary guide grooves 1010 produced on the internal walls of the upper part 101 of the body 10.

 The last operation consists in actuating the piston 21 using the loosening screw 20. To do this, the latter comprises a drive member constituted by at least one drive head in the form of a nut actuable by a key. or similar tool. Advantageously, this head is of the so-called "breaking" type, which makes it possible to apply a predetermined tightening torque, depending on the characteristics of the cables to be joined, in particular dimensional characteristics.

 In a preferred variant of the invention, represented in FIG. 1, the tightening screw is provided with two "breaking" heads, so as to apply a tightening torque of a first value, to achieve a tightening that the one can qualify as "approach", and a second tightening torque or final tightening, of a higher value. These heads are marked 23 and 22, respectively. Naturally, the upper head 23 is designed to apply the lowest torque. To do this, one can make grooves, respectively 230 and 220, more or less deep, between the two heads, 23 and 22, on one side, and the lower head 22 and the body of the screw 20, on the other. go.

 The piston 21 is held between the interior walls of the upper part 101 of the body 10. Advantageously, the piston 21 is constituted by a substantially rectangular rectangular block. Only the bottom wall 210 is slightly curved to best match the upper surface of the branch cable 4.

The screw head 200 20 rotates inside the piston block 21, so as to push it down, or more generally, parallel to the axis A around which the screw 20 is rotated.

 The underside 210 of the piston 21 exerts pressure on the branch cable 4 which is in turn driven towards the bottom of the cable clamp 1 and therefore in turn exerts pressure on the spacer 5. The tips or the like 50 then perforates the sheath 41 and comes into electrical contact with the core 40 of the cable 4. Similarly, the spacer 5, driven in the translational movement towards the bottom of the cable clamp 1 exerts pressure on the main cable 6 and the teeth 51 perforate the sheath 61 and come into electrical contact with the core 60.

 Under the effect of pressure, depending on the physical characteristics of each cable (stiffness, etc.), these will deform and occupy substantially the residual volume between, on the one hand, the piston 21 and the spacer 5, for the branch cable 4, and, on the other hand, between this same spacer 5 and the bottom 102 of the body 10 of the cable clamp 1. As has been indicated, the latter advantageously has a shape in "Vé", forming a receptacle. In Figure 1, there is shown the shape taken by the cables, 4 and 6, after crushing.

 Finally, in a preferred embodiment, there is provided a spring 3, or a similar member, disposed between the piston 21 and the end of the thread of the clamping screw 20. This makes it possible to catch the creep over time. sheath material 41 and 61, after tightening. Naturally, the end 200 of the screw 20 must allow a clearance of appropriate amplitude, so that the spring 3 exerts a repulsive force on the piston 21 to obtain the abovementioned compensation at any time.

 Although implicitly, until now, it has been assumed that the cable clamp device 1 according to the invention has only one clamping screw 20, several can be provided. Indeed, the number of these clamping screws, the length of the spacer and the value of the tightening torque, in particular, depend on the precise application, in particular on the dimensions, the weight of the cables to be joined and the resistance of desired contact.

 FIG. 2 illustrates an example of a cable clamp, referenced 1 ′, according to a second embodiment of the invention. Only the elements necessary for a good understanding of the invention have been referenced. In addition, the elements identical to those of the device in FIG. 1 have the same references and will only be described again as necessary.

 According to this embodiment, several clamping screws are provided, two in the example illustrated: 2 'and 2 ".

 Preferably, in this embodiment, at least one first clamping screw, 2 ", provided with a" breaking "drive head, 23", is provided, allowing clamping up to a tightening torque d 'a first value, so as to achieve the aforementioned "approach" tightening. There is also provided at least a second clamping screw, 2 ′, provided with a “breaking” drive head, 23 ′, allowing the tightening up to a tightening torque of a second value, so as to achieve the aforementioned final tightening. As before, the value of the breaking torque can be adjusted by making grooves in the screw bodies, 2 "and 2 ', respectively 230" and 230 ", more or less deep.

 Each screw acts on a piston which is associated with it, of which only one, 21, is visible in FIG. 2. These drive, in their translational movements towards the bottom of the body 10 of the cable clamp 1, the branch cable 4 and the spacer 5, the latter crushing the main cable passing 6.

 Advantageously, as before, provision is made for springs to compensate for the creep of the material of the sheaths 41 and 61, of which only one, 3 ′, is visible in FIG. 2.

 In both embodiments, the body 10 of the cable clamp 1 can be electrically insulated. To do this, an envelope of insulating material 7 is provided (a fragment of which is shown in FIG. 2), arranged on its outer walls of the body 10.

 This advantageous arrangement allows the use of several cable clamps side by side (case of sectoral cables for example), or even the manipulation of these under tension.

 On reading the above, it is easy to see that the invention achieves the goals it has set for itself.

 The cable clamp device according to the invention has a very simple structure, easy to handle and offers, however, a large set of functionalities. In particular, the body of the cable clamp is really one piece, that is to say without articulated parts, therefore cheaper and, a priori, more resistant. Only two parts are movable: the clamping assembly and the spacer. The provisions specific to the invention allow easy positioning inside the cable clamp and their maintenance inside thereof whatever the orientation in space of the cable clamp around the main passing cable.

 It should be clear, however, that the invention is not limited to the only examples of embodiments precisely described, in particular in relation to FIGS. 1 to 2. In particular, the number of clamping screws, as indicated, depending on the precise application, as well as the dimensions and other physical characteristics of the cable clamp.

 One can also consider, in a variant not shown, the derivation of two cables, one at each end of the cable clamp. It is probable that, for this type of application, a cable clamp according to the embodiment is the most suitable, that is to say an embodiment comprising several clamping screws.

 It would also be possible, without departing from the scope of the invention, to implement two or more separate tightening assemblies, each provided with one or more tightening screws, these assemblies all being threaded on the guide grooves provided on the internal walls of the cable clamp body.

 Finally, the materials used are those usually used in the field of applications targeted by the invention. Their choice remains within the reach of those skilled in the art. This aspect, in itself, is no different from known art.

Claims (10)

REVENIDICATIONS  1. Cable clamp device (1) with double insulation perforation, for derivation of a main cable passing (6) by at least one auxiliary cable (4), the two cables (4, 6) being able to be provided with an insulating sheath (41, 61), device comprising a body (10) provided with an open enclosure so that it can be positioned on the main passing cable (6), this pressing on the bottom ( 102) of the enclosure, device comprising at least one screwing member (2) exerting a pressure force on an assembly comprising, superimposed, the main passing cable (6), an electrically conductive spacer (5) provided with means (50, 51) for perforating said sheaths (41, 61) and the auxiliary cable (4), characterized in that said body (10) comprises, on the walls (100) of the enclosure, guide means (103) longitudinal of the spacer, in a direction parallel to said main passing cable (6), and holding inside said enclosure inte.  2. Device according to claim 1, characterized in that said body (10) has substantially the shape of a "U", in that in a lower part of the "U", it comprises shoulders (103) transverse, serving said guide of the spacer (5), and in that the spacer (5) is provided with two lateral grooves, of shape complementary to the shape of said shoulders (103), so as to be maintained inside said body (10), whatever the position in space thereof around said main passing cable (6).  3. Device according to one of claims 1 or 2, characterized in that said spacer comprises two flat side walls (53) intended to slide along the internal walls of said body (10) and two upper and lower walls (54, 55 ) provided with teeth (50, 51), allowing said sheath perforations, and provided with a curved profile, so as to match the surface of said main passing (6) and auxiliary (4) cables.  4. Device according to one of claims 1 or 2, characterized in that each of said screwing member (2) comprises a body (24), a clamping screw (20), a head (22, 23) for driving of the clamping screw (20) and a piston (21), in its lower part, exerting said pressure force.  5. Device according to claim 4, characterized in that said heads are provided with a "breaking" drive member (22, 220, 23, 230) so as to exert on said assembly comprising, superimposed, the main cable through (6), the spacer (5) and the branch cable (4), a tightening torque of determined amplitude.  6. Device according to claim 4, characterized in that said heads are provided with a double "breaking" drive member (22, 220, 23, 230) so as to exert on said assembly comprising, superimposed, the cable main pass (6), the spacer (5) and the branch cable (4), a first tightening torque, called "approach", of determined amplitude and a second tightening torque, called "final", d amplitude greater than said determined amplitude.  7. Device according to claim 4, characterized in that it comprises a first and a second clamping screw (2 ', 2 "), in that each of these clamping screws are provided with heads associated with first and second "breaking" driving member, in that the first "breaking" driving member exerts on said assembly comprising, superimposed, the main passing cable (6), the spacer (5) and the branch cable (4 ), a first tightening torque, called "approach", of determined amplitude and in that the second "breaking" drive member exerts on this same assembly a second tightening torque, called "final", d amplitude greater than said determined amplitude.  8. Device according to claim 4, characterized in that said body (10) is provided, in an upper zone (101) of said "U", on its inner walls, with longitudinal guide grooves (1010) and in that said body (24) of the screwing member (2) comprises, on its side walls, grooves (240) of profile complementary to these longitudinal grooves (1010), so as to be able to thread said screwing member (2) to the inside said body (10) by the lateral opening of the "U".  9. Device according to claim 4, characterized in that, the material making up said sheaths (41, 61) being liable to creep when it is subjected to compression, it comprises a spring (3) disposed between said piston (21) and the end of the screw (20) acting on this piston (21), exerting a repulsive force on it, so as to compensate for said creep.  10. Device according to any one of the preceding claims, characterized in that said body (10) is covered with an envelope (7) made of insulating material.