FR2719164A1 - Electrical connector for sealed cable crossing - Google Patents

Abstract

The connector includes a male contact (11), consisting of a pin attached to the extremity of a cable, and a socket 912) attached to a second cable (Ca2). Elastic blades (140) compress the socket which is protected by a tube (15).The tube presents an elastic clip (17,18) which holds the co-operating pin inserted in the tube through an opening (151). A sealing sleeve surrounds the pin.

Description

 The present invention relates to an element for connecting electrical cables to passive contacts.

It relates in particular to an element for connecting electrical cables to a device for hermetically crossing a partition or wall. It relates, more particularly still, to the crossing of partitions in an environment
"hostile". This term should be understood, in the context of the invention, in particular by "humid and pressurized environment". This is the case, for example, of an underwater partition.

 The invention will find a preferential, although not exclusive, application in the connection of hermetic bases without making plugs or in cable splicing in said environment.

The main needs to be met are as follows
- Electrical continuity;
- Significant axial mechanical retention, the amplitude is the same
order of magnitude than that encountered for crimping;
- Sealing allowing the pouring of an insulating material called "compound"
according to current Anglo-Saxon terminology; and
- Easy and quick connection in difficult areas.

 In the known art, attempts have been made to satisfy these requirements by various methods.

A first method consists in using feed-through devices comprising conventional waterproof multi-pin connectors
FIG. I illustrates a bushing device Dt according to the known art using screwable multispindle connectors C1 and C2. This type of device is well known and there is no need to describe it in detail. Only its main characteristics will be recalled. It includes a cylindrical body
Cp threaded into a hole made for this purpose in a partition C10 between the two sides of which must be established electrical connections. The central body Cp comprises a ring A forming a stop. The partition C10 is arranged between this ring
A and a locking element V. There are also provided seals J> O-ring or the like.

 The interior of the body Cp comprises a series of passive electrical contacts regularly arranged around a longitudinal axis a and of which only one, CO, has been shown so as not to overload the drawing. These CO contacts are in the form of a bundle of pins parallel to the axis d. The contacts are of the male type.

The isolation between the two sides of the partition C1 ,, which can be subjected to a significant pressure differential, is provided mainly by a "pearl" of Pva glass placed in a central zone of the device. The contact beam CO crosses this pearl Pv
The two connectors C1 and C2 are provided with female type contacts (not visible in the figure) paired with the ends of the CO contacts. These connectors
C1 and C2 are the ends of two cables Cal and Cn to be connected electrically, via the bushing device Dt. The connectors are provided with threads (not visible) which allows them to be screwed on the ends opposite the bushing device D1 . The electrical continuity between the cables Cal and Ca2 is then obtained at the end of the screwing operation. The connectors Cal and C are naturally provided with sealing means (not shown), which makes it possible to preserve the quality of the electrical contacts established.

 This type of device is well suited when frequent connection / disconnection operations are required. It is not the field targeted by the invention which is concerned with essentially non-removable interconnections.

On the other hand, its structure being complex, it is clear that such a device is expensive.

Finally, the various needs which have just been stated are only partially satisfied.

 Connections have also been made using metals with shape memory properties. However, the methods implemented have also proved to be expensive. It is also necessary to carry out repetitive so-called "education" cycles, which does not make it easy to make the connections.

 It was indicated that the connections made are by nature essentially permanent. However, this characteristic is not necessarily immutable. Indeed, different situations can arise: rupture of a cable, necessary lengthening thereof, etc. In all these cases, it will be necessary to modify the installation and, in particular the connections made. For obvious economic reasons, in most cases, it will be preferable to make a splice instead of carrying out the pure and simple exchange of the cable harness, damaged or to be extended. This facility therefore constitutes, in practice, an additional requirement which the device for connecting electrical cables must satisfy.

 Finally, as just mentioned, for industrial use, making the connections and the crossing device must be economical.

 The invention therefore sets itself the goal of a device for connecting cables to passive contacts which does not have the drawbacks of the prior art, while simultaneously satisfying the various needs expressed.

 The subject of the invention is therefore a connection element for at least one electrical cable on a passive contact of a first type, said electrical cable comprising at one end to be connected an electrical contact of a second type, characterized in that said electrical contact of a first type is a male contact and said electrical contact of a second type is a female contact comprising at least one elastic zone inside which said male contact is forcibly inserted over a determined length, in that it comprises a member forming a stop in an area external to said determined length, in that it comprises a protective enclosure secured at one end to the body of the female contact and open at its second end so as to allow the penetration of the end with connection of the male contact, the length of this enclosure being determined so that it covers at least the elastic region of the conta ct female and a zone of the male contact upstream of said stop when this is inserted in the elastic zone of the female contact and in that it comprises an elastic retention element, disposed in the protective enclosure and near said second end, authorizing the insertion of the female contact and prohibiting its removal by pressing on said stop after insertion.

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 an example of a crossing device according to the prior art, using connectors;
- Figure 2 illustrates an embodiment of an element for connecting electric cables to passive contacts according to the invention;
- Figure 2a illustrates a detail of the element for connecting electric cables to passive contacts according to a particular embodiment;
- Figure 3 illustrates a hermetic bulkhead crossing device comprising such elements;
- Figures 4a and b illustrates an example of possible configuration of passive electrical contacts.

 FIG. 2 illustrates an exemplary embodiment of an element for connecting electrical cables to passive contacts according to the invention. In reality, the electrical cable connection element, which will be called in the following contact element for reasons of simplification, is capable of two main embodiments, both shown in FIG. 1.

The main components of connection element I are as follows:
- A male contact 11 constituted by the end of a hermetic crossing pin or by a contact intended to be crimped on a cable or an electrical connection (not shown); this contact plays the role of the CO contact described by refrained in FIG. 1;
- A female contact 12, constituted for example by a split socket and its crimping end on a cable or an electrical connection C; the female contact comprises an elastic zone 14 allowing permanent pressure of the female contact (lugs or paddles 140 of the split socket);
- A protective tube lj limiting the arrows of the legs 140 of the split sleeve 12 or the movement of the elastic parts by acting (paddles) of the female contact 12; this tube is crimped at a first end (straight end in the example illustrated in FIG. 2) so as to make it integral with the body of the female contact 12 and folded down at its second end to ensure the retention of the contact 11 using of an elastic clip, that is to say of a clip according to the English terminology or of an equivalent part, references 17 or 18 according to two modes of realization which will be detailed below; it is however provided with a sufficient opening 151, at this second end, to allow the introduction of the male connector 11;
- A sealing sleeve 16, held in place because of its shape and which is adjusted by tightening around the contact 11 (left end in the example of the figure).

 As just mentioned, two main modes of execution are possible.

 According to a first embodiment, represented on the upper part of FIG. 2, the retention clip 17 is constituted by one or more tabs or strips 170 cut directly in the wall of the protective tube 15 and folded inwards. this tube. It suffices then that the body of the contact It is provided with a stop, for example an annular protuberance 110 with a steep wall on which the ends of the legs of the clip 17 come to rest. These forming a spring, prohibit the withdrawal of the contact male 11, once insertion has been completed.

 According to a second embodiment, shown in the lower part of FIG. 2, the clip is a self-contained piece 18.

 FIG. 2a more particularly illustrates, in partial cutaway, an exemplary embodiment of this retention clip 18. It comprises a substantially cylindrical and hollow body, 180, slid into the bottom of the tube 15 (on the right part, in the illustrated example) and in which the contact 11 is threaded. It also comprises one or more fins or retention tabs. In the example illustrated in FIG. 2a, the clip comprises two retention tabs, 181 and 182, arranged symmetrically with respect to the longitudinal axis A and folded towards the inside of the tube 180. The ends of the fins, 181 and 182, are supported previously horn, on the stop 110, or more precisely on the steep wall 1100 thereof. However, for the retention clip to be able to fully play its function, it must not be able to move in a direction parallel to the axis A or at least that the amplitude of the movement is limited. To do this, a stop is provided in the wall of the protective tube 15, for example a radial boss 150.

 We will now describe an example of a preferred application of the connection element 1 to a hermetic bulkhead crossing device. FIG. 3 describes such a device.

 In what follows, the identical or at least similar parts to those which have just been described, in relation to FIG. 2, bear the same references and will only be re-described as necessary.

 It is assumed, in the example illustrated, that it is a submarine partition 3 subjected to a high pressure differential between its two walls, that is to say between the media M1 and M2 separated by said partition 3.

The crossing device 2 comprises a main body 20 having the shape of a hollow cylindrical member and introduced into an orifice 300 with which the partition 3 is provided and of dimensions adapted to the outside diameter of the tube 20. The tube 20 is made integral with the partition 3, by a welding thread 30 for example, which also ensures sealing,
The actual crossing device will be introduced inside this external protective tube 20. It will be a question of establishing interconnections between, on the one hand, male contacts or pins 1 1 and, on the other hand, two bundles of cables located on either side of the partition 3. To avoid overloading the drawing, only one, aa> has been shown (on the right-hand side of the figure, in the example illustrated).

 One of the main sub-assemblies making up the crossing device 2 comprises a support body 22 in the form of a ring which can slide into one of the ends of the tube 20 (straight end in FIG. 3). This is provided with a central opening 220, which is also advantageously circular.

This central opening 220 is filled with molten glass 5 (or an equivalent material forming a hermetic barrier, such as ceramic) in which elongated male contacts or pins 11 have been inserted. These contacts 11 extend in a direction substantially parallel to axis A or axis of symmetry of the crossing device 2.

The operations necessary to connect the harness C a of cables C with the contacts 11 are as follows:
This bundle Ca is first of all threaded, conventionally protected by a sheath G, into the tube 20 by one of its ends (left end in the example described) and it is brought out of this tube 20 by its other end.

 A series of steps is then carried out consisting in making, one by one, the interconnections between the different cables C, |, of the cable bundle C a and the male contacts 11. To do this, the ends of the cables C are crimped, during from a preliminary step, to female contacts 12 conforming to those which have been described with reference to FIG. 2. These female contacts 12 have been provided with their protective tube 15, retention clips, 17 or 18, according to the embodiment, and the protective sheath 16 (see Figure 2).

 The connection is definitively established simply by inserting the female contact 12, through its elastic zone 14 (lamellae 140), on the male contact 11, until the retention clip, 17 or 18 ( figure 2).

 This operation is repeated until all the cables C are connected to the appropriate male contacts 11, according to the interconnection diagram to be produced.

 A protective chamber 21 is provided for the interconnection zone, that is to say connection elements 1 according to the invention. This protective chamber 21 is in the form of a hollow cylindrical part whose internal diameter is determined so that it can be threaded, by one of its ends, onto the sheath G of the ca beam of Ca2 cables. It comprises at the opposite end a thread 210 complementary to a thread 221 produced in the central area of the support 22. The protective chamber 21 can therefore be secured, by screwing, to the support 22, when the connection steps are completed. Naturally, in most cases, it will be necessary to thread the protective chamber 21 onto the sheath G before making the said connections of the male contacts it and female 12.

 Advantageously, a guide piece 27 is also provided, which is also slipped over the sheath G before the connection operations. This guide piece 27 comprises an annular central body 270, the outside diameter of which is determined so as to allow its insertion. inside the tube 20, and a flange 271 of larger diameter. As a result, the part 27 cannot be introduced entirely into the tube 20. It then forms a plug when the flange is pushed back towards the mouth of the tube 20.

 Once the interconnection operations have been completed, as indicated, the protective chamber 21 is screwed onto the support 22. Then a step of filling the interior of this chamber 21 is carried out using a soft insulator 4 or "compound" according to English terminology. To do this, there is provided a filling orifice 211 drilled in the wall of the chamber 21. To evacuate the overflow, there is advantageously provided another orifice 212, which may be of smaller diameter. During the introduction, the insulating material 4 is in the liquid phase or in the pasty state. Among the materials that can be used, silicone is perfectly suited for this use. The sheath 16, which is provided with each connecting element 1, makes it possible to protect the electrical contacts by preventing the infiltration of the insulating material 4 between the surfaces in contact and thus ensuring electrical continuity.

 The subsequent steps consist in definitively fixing the set of male contacts 11 (on its support 22) and female contacts 12, the latter being crimped onto the ends of cables C> inside the tube 20, hermetically.

 In a preferred variant embodiment, the tube 20 actually comprises two zones, 200 and 201, distinguished by their respective internal diameters. The zone 201 (on the right, in the example illustrated) is provided with a larger diameter, that is to say equal to or slightly greater than the outside diameter of the support 22. Under these conditions, the latter can be introduced inside the tube 20 until the start of the zone 200. However, before proceeding with this introduction, there are sealing means 26 between the support 22 and the wall forming a step between the zones 200 and 201 of the tube 20. An asbestos seal is suitable for this function.

 To ensure final sealing, this seal 26 is tightened against the step 202. To do this, a clamping nut 23 is used. This is first screwed onto the support 22 using a thread 230, provided for this purpose and complementary to a thread 222 produced on this support The end of the tube 20 also includes a thread 203, on the inner wall. Finally, the nut 23 has an additional thread 231, complementary to this thread 203. There is interposed between these two parts, 22 and 23, sealing means. The latter are advantageously constituted by a bevelled washer 25 and an O-ring 24 which fills, by crushing, the cavity left free between the parts 22 and 23, when the nut 23 is tightened.

 As has been pointed out, only one bundle Ca of cables C has been shown, so as not to overload the drawing. fl it is naturally necessary, before proceeding to the final fixing (by screwing) of the central body 22 inside the tube 20, to carry out similar operations of interconnections between the straight ends (in the illustrated example) of the male contacts 11 and cables (not shown) from the middle M2.

 It has been implicitly assumed that the pressure prevailing in the medium M1 is higher than that prevailing in the medium M2, the medium M2 possibly being, for example, a marine environment and the medium M1 inside an underwater enclosure.

It will therefore be easier to access the zone 201 of the tube 20. Under these conditions, it may be unnecessary to provide, on this side of the partition 3, a protective chamber similar to the chamber 21.

 However, this particular arrangement in no way limits the scope of the invention, it is just as well possible to provide a chamber for protecting interconnections, symmetrical with the chamber 11 with respect to the support 22 and to the glass wall 5 traversed by the contacts. 11. It is this wall 5 which ensures, as has been indicated, most of the sealing and which supports the pressure difference between the two media. It is this arrangement which authorizes, in particular, the use of a soft insulator 4 in the connection zone of the male 11 and female 12 contacts.

 FIGS. 4a and 4b illustrate an example of a possible configuration of male contacts trapped in the glass wall 5 arranged in the central opening 220 of the support 22. More precisely, FIG. 4a represents the support 22 and its contacts, seen from the side, and FIG. 4b, this same support 22 and its contacts, seen in section along Axa '.

 In the example illustrated in these figures, the male contacts 1 1 are arranged in circular rings concentric with the axis A. In addition, the length of the contacts 1 I advantageously decreases from the center (axis A) towards the periphery, for example linearly , the contacts of each ring all having the same length in the example illustrated in the figures. Still in the example illustrated, the contacts of the two central rings have the same length. However, this is only a purely arbitrary choice.

 The arrangement consisting in providing the contacts with variable lengths, decreasing towards the periphery, is advantageous in that it facilitates the connections between cables (case, see Figures 2 and 3), provided with their female contacts 12, and the male contacts 11. It suffices precisely to carry out the connection operations, starting with the contacts of the central rings and ending with the contacts of the peripheral rings. The gradient facilitates these operations, even if a large number of contacts are to be connected, for example more than a hundred contacts.

 It is understood that the device 2 (Figure 2) can be perfectly standardized. In this case, several types of supports 22 are provided, essentially differing in the number of male contacts 11. It is also possible to use supports comprising the same number of male contacts 11 and to wire only part of them.

 To fix the ideas, in the particular embodiment illustrated by FIGS. 4a and 4b, the number of contact rings 11 is equal to seven, with the following distribution by rings: two, eight, fourteen, twenty, twenty-six , thirty-six and thirty-six contacts (from the center to the periphery).

Still to fix ideas, and without this being able to constitute any limitation of the scope of the invention, the following technical characteristics can be associated with the bushing device 2 and with the passive contact connection elements II according to the invention:
- overall length of device 2 (tube 20): approximately 120 mm
- diameter: 30 mm approximately
- wall thickness: approximately 7 mm
- tube material 20: steel
- soft filling insulation: elastomer
- protection tubes 15: stainless steel
- protective sleeves 16: elastomer, silicone or plastic
waterproof
- male contacts Il and female 12: brass or gilded ferro-nickel
- diameter of male contacts 11: typically 1.35 mm
- lengths: stepped between 17 and 47 mm in the example illustrated by
Figures 4a and 4b
- retention clips 17 or 18: beryllium or stainless steel
It is easy to understand, following the description which has just been given of the element for connecting electric cables to passive contacts and of its preferred application to a device for hermetically crossing a partition, that the invention perfectly fulfills the goals she had set for herself.

 The crossing device provided with connection elements in accordance with the invention retains the insulation characteristics between lines (cables) provided by a complete connector, as well as the other qualities associated with this type of device, while economically making interconnections. non-removable.

 Although particularly suitable for applications using hermetic passage devices, the invention cannot be confined to this single type of application. It also applies to all cases where splicing or extending a cable is preferable, whether for economic reasons or for ease of access, to the complete exchange of said cable.

 Finally, it should be clear that the invention is not limited to the embodiments precisely described, in particular in relation to Figures 2 to 4b. In particular, the materials and the geometrical data were indicated only with the sole title of examples of concrete realizations. One can also, without departing from the scope of the invention, operate any technological choice within the reach of a person skilled in the art.

Finally, in an alternative embodiment not shown, a single end of male electrical contacts could be connected to cables (Ca)
The other end, for example the end located in the middle M2, inside an underwater enclosure, in the example illustrated in relation to FIG. 3, could then be conventionally connected to connections electric. by welding for example.

Claims (9)

 1. Connection element for at least one electrical cable (Ca2) on a passive contact of a first type (11), said electrical cable comprising at one end to connect an electrical contact of a second type (12), characterized in that said first type electrical contact (11) is a male contact and said second type electrical contact (12) is a female contact comprising at least one elastic zone (14) inside which said male contact (11) is forcibly inserted over a determined length, in that it comprises a stop member (110, 1100) in an area outside said determined length, in that it comprises a protective enclosure (15) integral at a first end to the body of the female contact (12) and open at its second end so as to allow the connected end of the male contact (il) to penetrate, the length of this enclosure being determined so that it covers at M oins the elastic zone (14) of the female contact (12) and a zone of the male contact (11) upstream of said stop (110, 1100) when the latter is inserted in the elastic zone (14) of the female contact (12 ), and in that it comprises an elastic retention element (17, 18), disposed in the protective enclosure (15) and close to said second end, allowing the insertion of the female contact (12) and preventing its removal by pressing on said stop (110, 1100) after insertion.  2. Connection element according to claim 1, characterized in that the retention element (17) consists of at least one strip (170) cut in the wall of said protective enclosure (15), folded inwards of this enclosure (15) to form an elastic clip.  3. Connection element according to claim 1, characterized in that the retention element consists of a tubular member (18) disposed in the protective enclosure (15) and near said second end (151), comprising at least one elastic strip (181, 182) cut in its wall and folded inwards to form an elastic clip and in that the wall of this enclosure is further provided with a stop (150) limiting the amplitude of the displacement of the tubular member (18) between said second end (151) and this stop (150).  4. Connection element according to any one of claims I å 3, characterized in that it further comprises a protective sleeve (16) made of waterproof material covering at least said protective enclosure (15).  S. Connection element according to claim 1, characterized in that the end of the female contact (12) opposite to the elastic zone comprises crimping means (13) of the end of the electric cable (Ca2).  6. Connection device according to claim 1, characterized in that said elastic zone (14) of the female contact (12) consists of a split socket comprising tabs (140) exerting constant pressure on the male contact (11) after insertion.  7. Hermetic passage device (2) of a partition (3), characterized in that it comprises at least one element for connecting at least one electric cable (Ca) to a passive contact (11) according to any claim 1 to 6.  8. Hermetic passage device (2) according to claim 7, said partition (3) being disposed between two media (M1, M2) subjected to a pressure differential, characterized in that it comprises a support (22) comprising several male contacts (11) embedded in a bulkhead of molten glass (5) to which the ends of cables (cl2) connected with said female contacts (12) are connected, said partition being disposed in a central orifice (220) of the support (22) and forming a tight barrier between said media (mol, M7), in that it further comprises a protection chamber (23) of the male (11) and female (12) contacts and in that said protection chamber (21 ) is filled with a soft insulating material (4).  9. Hermetic feed-through device (2) according to claim 8, characterized in that said male contacts (11) are distributed on concentric rings and in that the length of these male contacts (11) decreases from central rings towards the rings peripherals, the male contacts (11) of the same ring all having an identical length.  10. Hermetic passage device (2) according to claim 8, characterized in that said protective chamber (21) comprises means for fixing by screwing (210, 221) on said support (22).  He. Hermetic passage device (2) according to claim 10, characterized in that it comprises an external tubular body (20) passing through said partition (3) and hermetic fixing means (26, 230, 24, 25, 23) by screwing said support (22) and protective chamber (21) inside the bermetic feed-through tube (20).