FR2686461A1 - Sealed electrical connection device - Google Patents

Abstract

- Connection assembly for the purpose of making an electrical connection, comprising a male plug (2) carrying pins (26a, 26b) and a female socket (1) whose contacts (7) under voltage are capable of receiving the bearing surface of the pins coming from the plug and are engaged in openings (18a, 18b, 18c, 18d) provided in the female socket (1), and the assembly is characterised by sealing means arranged on the socket (1) and capable of insulating the contacts under voltage, both in the stand-by position of the socket with no plug inserted and in the position in which the plug is engaged in the receiving socket, and these means are constituted, on the one hand, by micro-valves (19) capable of closing off the said openings (18a, 18b, 18c, 18d) of the socket in the absence of the plug and in freeing these openings under the thrust of the pins (26a, 26b) in the position of engagement of the plug, and, on the other hand, by at least one seal (15c) arranged on the inner wall (15b) of the receiving socket and capable of receiving the bearing surface of the outer wall (23b) of the plug, thereby isolating the interface between plug and socket in their engagement position.

Description

The invention relates to a connection assembly for ensuring an electrical connection between a movable male plug carrying pins and a female base comprising live studs.

The invention relates more specifically to such an electrical connection device intended to ensure not only protection of the studs under voltage against any damage and any accidental contact liable to cause accidents, but also and above all to ensure total hermetic isolation of the together in relation to the external environment and in particular in relation to sources of humidity liable to establish poor contact or a short circuit.

According to another object of the invention, the connection assembly between plug and base under voltage allows an explosion-proof electrical connection and usable even in a flammable or explosive environment.

The invention also aims to allow the establishment of a female socket whose studs are energized, being connected to the supply network, the female socket thus available and ready to accept a male plug being however isolated as well in the released position and in the absence of any male plug.

connected only in the presence of such a plug placed on the socket while allowing direct access to the plug without prior manual release of a member such as a protective cover.

Safety connection devices are known which include a front plate obscuring the live studs. Openings on the wafer can receive the pins of the plug, the latter coming into position facing the studs under tension only after combined rotation of the wafer and the plug.

This is the case of the devices described in the British patents 1,198,640 and German 1,252,778.

However, these concealment devices do not seal the elements before or after the connection.

The invention allows the concealment of live studs but at the same time it aims to provide other security by hermetically insulating the live parts, both at the socket when it is free and in the standby position. only at the socket after receiving the connected plug.

In current devices, in fact, the openings being accessible can receive water splashes, all the more so as generally the sockets are positioned at a lower level along a wall.

Safety devices are already known, in particular by the presence of a protective cover in the case of an outlet located outside; the folding hood can however deteriorate or lose its hermetic character, all the more easily as it is located outside and in the protruding position, therefore ready to receive physical aggressions on the occasion of shocks causing a malfunction and consequently a loss of the sealing of the socket then exposed to the weather.

However, the invention makes it possible to have a socket devoid of any cover, directly accessible and therefore open to the penetration and engagement of a pin-carrying plug, while this socket or this female base remains insulated and sealed relative to in the outdoor environment and therefore remains insensitive to water splashes or the penetration of moisture which does not risk in these conditions reaching the live terminals and establishing a false short-circuit contact.

To this end, the invention relates to a connection assembly for an electrical connection comprising a male plug carrying pins and a female base and whose live studs are capable of receiving support from the pins coming from the plug and engaged in openings provided on the female base, and the assembly is characterized by sealing means arranged on the base and able to isolate the studs under tension, both in the standby position of the base without plug in place and in the position of the plug engaged on the receiving base and these means consist on the one hand of micro-valves capable of closing said openings of the base in the absence of a plug and of releasing these openings under the thrust of the pins in the position of engagement of the plug, and on the other hand by at least one seal placed on the inner wall of the receptacle base and capable of receiving the support of the outer wall of the plug ensuring isolation t the interface between plug and base in their engagement position.

More specifically, the female base comprises a frustoconical housing flared outwards capable of receiving the frustoconical body of complementary shape of the plug engaged with self-centering in the receptacle housing of the female base, and this female base comprises a circular seal located on the inner wall of said frustoconical housing thereby ensuring the seal between the plug and the base in their position of mutual engagement.

Advantageously, the seal includes a flexible lip oriented towards the inside of the housing and capable of being crushed and deformed by the body of the plug when the latter is put in place on the receiving base.

Advantageously, the shutter valves ensuring the watertight closure of the penetration openings of the pins carried on the plug consist of shutters with hemispherical head recalled on their seats opening outwards each by an opening suitable for receiving the penetration of the pins coming of the plug, the hemispherical head shutters being able to be pushed towards the inside of the base against a return spring by the pushing of the pins when they engage in the opening previously closed by the said shutters and the erasing of the shutters allowing the engagement of the pins in said opening to reach the studs under tension.

According to a further development of the invention, the power supply wires allowing the connection of the plug and / or the base penetrate into the corresponding element with sealing means ensuring the insulation of. the output of the supply wire made up of a cable under sheath.

Advantageously also, the plug and the base comprise locking means in their position of mutual engagement and constituted by projecting lugs arranged on the plug and penetrating into receptacles of the base forming a bayonet locking device by angular rotation of the plug brought into place in the housing provided on the receiving base.

According to an alternative embodiment, the openings allowing the pins to penetrate against the erasure of the valves are arranged on a rotary disc mounted in the bottom of the housing provided on the base, the disc being able to be rotated with the plug in its locking movement by a bayonet device, the pins then being brought into contact with the studs under tension, and the disc has sealing means on its periphery coming into contact with the wall of the base and said sealing means are constituted by the peripheral wall of the disc (according to a curved elm bevel) the disc defining a segment of a sphere, said wall bearing on the frustoconical fixed wall substantially complementary to the base, the disc being pushed against this frustoconical fixed wall of support by the thrust of the valves bearing on their seats and kept under tension by their return springs, the support of the peripheral wall cu rviforme of the disc being made on the fixed wall tangent at any point to said curviform peripheral wall of the disc.

Advantageously, the disc has four openings for the reception of four pins distributed in corresponding positions on the plug, the openings of the rotary disc and the corresponding pins being arranged equidistantly on the disc and on the plug.

According to another development of the invention, the plug and the base comprise two members cooperating with each other and consist of a surface unevenness on a part of the walls of the plug and of the base respectively coming into contact, these surface inequalities marking a force passage in the final face of the plug blocking in its locking position by the bayonet locking assembly, this force passage thus emphasizing by the slight tactile resistance felt manually and supplemented by an audible click upon arrival in position of final engagement of the plug on the base and corresponding to the electrical contact between pins and studs under voltage.

Other characteristics and advantages of the invention will emerge from the description which follows and which is given in relation to a particular embodiment presented by way of nonlimiting example with reference to the appended drawings.

Figures 1 and 2 show sectional views respectively of the base (Figure 1) and the plug (Figure 2) and along lines I - I of Figure 5
Figure 3 shows a perspective view with broken away
partial of the base
Figure 4 shows a perspective view of the form.

Figure 5 shows a schematic plan view of the interior of the base.

Figure 6 shows a plan view of the face of the plug facing the base.

Figures 7 and 8 respectively represent sectional views of intermediate adaptation devices capable of being inserted between a base according to the invention and a conventional plug (Figure 7) and between a plug according to the invention and a conventional base ( Figure 8).

According to all of the Figures, it can be seen that the device comprises a base 1 and a plug 2 capable of being engaged in the base 1.

The assembly shown here constitutes a remote connection device of the "extension" type.

It being understood that the connection of the invention is not limited to this presentation.

The base 1 could be constituted by a wall socket immobilized on a wall; and the wall outlet is then able to receive the engagement of the movable plug 2.

But, conversely, the plug 2 could be immobile and fixed, being for example disposed on the wall of an electrical appliance, and capable of receiving the engagement of the base 1 itself mobile being disposed at the end of a wire or electrical connection cable.

The female base 1 consists in the example produced of a chamber 3 insulated in a sealed manner with respect to the external environment as will be described below.

This chamber is formed in the main shell body 4 which has an opening 5 for the engagement of the cable 6.

A sealing device of the "cable gland" type is provided to seal the passage of the cable 6 in the opening 5 and it is in particular constituted by a seal 5a, in particular neoprene of hardness 30 to 50 shores, compressed by the annular screw 5b with interposition of a washer.

The cable 6 is immobilized in position by the flange 9 in a manner known per se and the wires which it contains 6a, 6b are by their stripped ends 6c brought into the position of electrical contact on the receiving pads 7.

The chamber 3 is insulated by the transverse wall 8 with the interposition of a circular seal 10 made of elastomer, in particular neoprene (hardness 60 shores). This quadrangular section joint is crushed in a rebate
The pads respectively 7a, 7b, 7c (Figure 3) are advantageously held in place by a support plate 11 and which has recesses engaged on a groove provided on the body of the pad 7 and with parallel edges to prevent rotation of the pad during tightening of the screw immobilizing the stripped end 6c of the supply wire.

The support plate - 11, shown in the view of FIG. 1, is itself held in place against the transverse wall 8 by the screw 12 and this support plate which is made of epoxy or polyethylene resin loaded with glass fibers may experience bending away from the transverse wall; which allows flexibility in the positioning of the pads 7 may experience a slight decline especially when arriving in the contact position of the pins of the connected plug, as will be described below.

The screw 12 is advantageously covered by an insulating cover integral with the wafer 11. The studs 7 abut by their head on the underside of the disc 17 described below and transfer the thrust of the spring to this disc 13. Advantageously, provision is made four pads 7, two of which are live conductive pads, a third pad can be assigned to the ground and a fourth has no electrical activity but serves to ensure a balanced and distributed pressure around the periphery of the disc 17 described below . The number of pads is not critical and depends on the type of electrical connection desired and the supply current. The studs will be arranged equidistant from each other to equalize and distribute the thrust carried over to the disc 17 evenly.

The base 1 extends towards its open face for the engagement of the plug by the bodies of revolution 14, 15 attached to the transverse wall 8 by any suitable means, in particular microwave or ultrasonic welding.

A known system of studs engaged in a housing makes it possible to locate the correct positioning during the mounting and assembly of the parts.

The annular body 14 has an inner wall which is flared in the direction of the transverse wall 8, thereby defining a female inverted frustoconical wall 16 for the support of the bevelled and curved edges 17a of the central disc 17.

The support of the disc by its bevelled and curviform edges is done on the inverted frustoconical wall thus tangent in all points to the curviform wall of the disc 17a, one thus obtains a peripheral circular line of contact and obturation between disc and fixed wall d 'support 16 whatever the position, possibly slightly inclined, of the disc as a function of an accidentally uneven thrust received from the shutters 18 mounted on spring 20 and studs 7 reporting the thrust of the springs 13.

This disc, shown in plan in FigureS, has four openings 18a, 18b, 18c, 18d distributed equidistantly on its surface and which constitute the access openings for the pins coming from the plug 2.

The openings 18 (FIG. 1), and identified under the references 18a, 18b, 18c and 18d in FIG. S, are closed by a valve made up of a shutter with a curviform head 19 coming to rest on its receiving seat of frustoconical profile, the head being pushed back onto its seat by the lower spring 20 located in the housing 21 itself formed in the transverse wall 8, this spring being in abutment at its base in the blind bore provided in the body of the shutter.

The four openings 18a, 18b, 18c and 18d thus thus each contain a curviform head forming a valve and the thrust of which, under the tension of the lower return spring 20, pushes the whole of the disc, by a pressure uniformly and equally distributed, over its periphery in the sealed contact position of the bevelled and curved peripheral wall 17a of the disc against the receiving support wall 16 coming from the annular body 14.

It can be seen that, under these conditions, the open face of the female base is sealed with respect to the external environment since the disc 17 closes this wall, itself in sealing contact around its periphery, and the openings 18 which it comprises being themselves closed by their individual valves.

The annular body 14 is itself surmounted by the ring 15 defining an internal bore 15a forming the receptacle housing for the plug 2.

This bore has a frustoconical wall flared outwards 15b carrying a peripheral sealing gasket 22 made of elastomer such as neoprene with shore hardness close to 60.

The socket 2 is itself constituted by a body of revolution with a frustoconical base 23.

This body defines an interior chamber 24 into which the cable 6 ′ penetrates with a known sealing assembly 25.

The chamber is closed frontally by the wall 27 crossed by equidistant pins, in particular three or four in number and corresponding to the positioning of the openings 18a, 18b, 18c, 18d of the base.

The seal between the bottom 23a and the main body 23 is obtained by crushing the circular seal 10 'of quadrangular section and housed in a receiving rebate
On these pins 26 at least two are electrically active for the electrical connection to the pads 7 of the base under supply current; another pin can serve as an electrical contact for earth or grounding while a fourth pin can be electrically inactive and used only for clearing the openings 18 of the disc 17 in order to ensure an equal distribution of the pressure on this disc during the retraction movement of the curved head valves 19 under the thrust of the four pins and the engagement of the plug.

The plug comprises at the base of the frustoconical wall 23b diametrically opposite lateral protuberances forming lugs 23c (preferably of unequal dimensions to allow a single direction of engagement) constituting with the housings provided at the base of the bore 15a of the annular body 15 a bayonet locking assembly.

This secures the plug in its housing.

At the same time, the frusto-conical wall 23b of the main body 23 of the plug comes to bear on the complementary frusto-conical wall 15b 22 of the base with interposition and crushing of the circular seal thereby ensuring the tight closure of the interface between the plug and the base .

It can thus be seen that, at the very moment when the openings 18 are released by the penetration of the pins, that is to say when the sealing of the female base is no longer ensured, this sealing is found at the same time and immediately reconstituted by closing the plug / socket interface at the seal 22.

Thus and advantageously, an open base is obtained and ready to receive an electrical connection plug which has perfect electrical safety.

The studs 7 are in fact obscured by the disc 17 and especially by the valves 19, avoiding any access and any unwanted and accidental electrical contact liable to have serious consequences for the studs under voltage; while the sealing and hermetic protection of the pads is ensured, the latter being insulated in a sealed manner from the open housing 15a, any projection of water being prevented from penetrating by the sealed contact of the peripheral wall of the disc 17 bearing on the tangent complementary wall 16 under the pressure of the springs 20 and 13 which thus ensure the maintenance, the tension necessary for the closing and the sealed isolation of the base both at the openings 18 and at the peripheral edge 17a of the disc 17 on its bearing surface 16.

And as soon as the plug is engaged, the openings 18 then being released, we obtain as previously pointed out a tight closure at the peripheral seal 22.

The final rotation of the plug when closing the device and the bayonet locking causing the rotation of the disc and the plug and bringing the electrically active pins into the contact position on the live studs 7, the latter being under electric tension d 'on the one hand but also under the mechanical and elastic tension of the part 11 and even under tension of the return springs 13, so that one obtains through this elastic support a satisfactory electrical contact between pins and studs.

Advantageously and as can be seen in FIG. 4, it is possible to provide, between plugs and bases, means for controlling the arrival of the plug in its contact position at the end of rotation during the engagement of the bayonet locking of the pins 29, 29 'in their housing 29a on the base.

These locating means can consist of simple visual indicators making it possible to note the alignment of the two marks respectively on the plug and on the peripheral edge 15d of the annular body 15, the correspondence between the two marks noting that the studs are necessarily in position receiving and supporting the pins of the plug, the electrical contact is therefore established.

According to one development, one could provide on the plug and / or on the base a diode visible externally and then electrically connected to the two studs, through the corresponding pins, thereby establishing by the luminescence of the diode the existence of electrical contact.

Finally, provision has also been made to have on one or both elements brought into contact with protuberances or reliefs 28 capable of cooperating with each other to achieve a force passage allowing the user to note a slight resistance at the end of the stroke, the passage of this resistance signaling by the tactile sensation that the plug has reached its final locking position.

At the same time, provision could be made to arrange these raised protrusions on elastically deformable elements which are capable, during their mutual passage, of being elastically erased to facilitate passage and of causing a sound click allowing the user to still note by ear that the end of travel position has been reached and that contact is therefore normally established; these simple means allow the user in case of malfunction of the device to ensure that the bad connection does not come from a bad position of the plug on the base but from the device itself.

For example, the protuberance or relief 28 is disposed on the outer edge of the hollow stud 23c to allow a certain flexibility of the outer wall 23d carrying the relief 28.

In addition the elements in relief 28, cooperating with each other to note the immobilization of the plug in the base in the connection position also provide a simple locking means preventing accidental escape of the plug from its connection position for example following pulsations which could risk causing parasitic rotation of the plug by causing the pins to move relative to their contact position on the live studs; this could be observed, for example, if the connection of the invention is positioned on an electrical device comprising a motor, the vibrations or even slight vibrations of which can affect the connection.

It will be noted that if the device according to the invention achieves a safety assembly preventing accidental access to the energized stud by a metallic member manipulated for example by a child, and if it also offers additional safety by protection against the humidity or water infiltration, as previously explained, it adds to these advantages interesting properties in particular in the case of the use of the connection in an explosive atmosphere.

It is seen in fact that, at first, the plug engages on the base by occupying all the free space of the capacity and consequently driving out the atmosphere of this open capacity until the contact of the wall peripheral of the plug is made on the circular joint 22; in this position there is then obtained a hermetic isolation from the external environment of the interface between the plug and the receiving base; and during this time no electrical contact has yet taken place; thereafter, the rotation of the plug towards its locking position by the bayonet device will bring, as previously explained, the pins into contact with the pads under tension; so that the arc effect and the spark which can occur in the final phase of the approximation of the pins and the studs takes place in a closed and isolated medium, consequently preventing any ignition of the flammable or explosive medium.

Such circumstances may occur accidentally as a result of gas leaks; but the risks of the presence of such a flammable or explosive medium can be found permanently in technical premises (garages, service stations, factories or workshops working with powdery products, or in powdered product storage facilities).

Figure 7 shows a development of the invention relating to an intermediate adaptation device allowing the connection between a base of the invention and a plug carrying conventional pins.

To this end, the intermediate adaptation device consists of a body of revolution made of insulating material 123 comprising a first transverse face adaptable on a base according to the invention and comprising for this purpose a plurality of pins 126 suitable for being engaged in the openings 18 of the disc 17 disposed on the receiving base, the pins 126 being able to come, after rotation of the body 123, in contact with the studs 7 under tension of the base, the intermediate body has an opposite transverse facet provided with at least two twin housings the walls of which are made of conductive material and which extend the electrical contact with said pins 126, the twin housings 31 being able to receive the pins of a conventional electrical connection plug; and the body of revolution comprises a peripheral wall 123b of frustoconical shape capable of being engaged in the housing 15a complementary to the base and comprising at its periphery lugs to allow bayonet locking of the intermediate body on the base according to the invention.

It can be seen from FIG. 7 that a pin 126a disposed on the first transverse face coming into contact with a base according to the invention is extended on the opposite face by a pin 126b arranged in alignment and which corresponds to the grip of protruding earth capable of being engaged in the housing 32 of the conventional plug.

A peripheral seal 33 advantageously completes the intermediate body to allow a tight integration of the conventional plug in the intermediate body.

Figure 8 shows another development of the invention relating to a connection device between a conventional base and a pin carrying plug according to the invention.

And the device here consists of a body of revolution made of insulating material comprising a first transverse face 34, capable of being engaged on a conventional base, carrying pins 131 arranged in alignment and in electrical contact with the pads 107 mounted at longitudinal sliding on an intermediate plate and the springs 113, an engagement by pinching 35 allowing the continuity of the electrical contact and a relative flexibility of movement between the fixed pin 131 and the stud under corresponding tension 107, the device comprising an opposite transverse face offering a housing 115 suitable for receiving the engagement of a plug in accordance with the invention and the bottom of which is occupied by a disc 117 provided with the openings closed by the curvature-shaped clappers and thus capable of receiving the engagement of the sheet 2 according to the invention.

The materials used in the context of the implementation of the component elements of the invention, in particular the bases and plugs, can be adapted to requirements; we will recommend a known synthetic material, such as
Loaded PVC to prevent heat distortion.

It will be noted that in the description of the adaptation devices corresponding to Figures 7 and 8, we have not included the list of elements which include the bodies previously described for the plug and the base of the invention; the intermediate member of FIG. 7 comprises a face 127 conforming to the corresponding face of the plug according to the invention; while the intermediate member of FIG. 8 has a face corresponding to the upper part of FIG. 1, the members of which are identical to the members of the base of the connection assembly according to the invention.

Claims (9)

1 - Connection assembly for an electrical connection comprising a male plug (2) carrying pins (26a, 26b) and a female base (1) of which the studs (7) under voltage are capable of receiving the support of pins coming from the plug and engaged in openings (18a, 18b, 18c, 18d) provided on the female base (1), and the assembly is characterized by sealing means arranged on the base (1) and suitable for isolate the studs under voltage, both in the standby position of the base without plug in place and in the position of the plug engaged on the receiving base and these means consist on the one hand of micro-valves (19) capable of closing said openings (18a, 18b, 18c, 18d) of the base in the absence of plug and to release these openings under the push of the pins (26a, 26b) in the position of engagement of the plug, and on the other hand by at least one seal (15c) disposed on the inner wall (15b) of the receiving base and capable of receiving the 'support of the outer wall (23b) of the plug ensuring the isolation of the interface between plug and socket in their engagement position. 2 - Connection assembly according to claim 1, and characterized in that the female base (1) comprises a frustoconical housing (15a) flared outwards capable of receiving the frustoconical body of complementary shape (23b) of the plug engaged with self-centering in the receptacle housing of the female base, and this female base includes a circular seal (15c) located on the inner wall of said frustoconical housing thus ensuring the seal between the plug and the base in their engagement position mutual. 3 - connection assembly according to claim 2, and characterized in that the seal (22) has a flexible lip oriented towards the inside of the housing and capable of being crushed and deformed by the body of the plug during the establishment of the latter on the receiving base. 4 - Connection assembly according to one of claims 1 to 3, et.caractérisé in that the shutter valves (19) ensuring the sealed closure of the openings (18a, 18b, 18c, 18d) of penetration of the pins (26a , 26b) worn on the plug (2) consist of curviform head shutters  recalled on a frustoconical seat open to the outside each by an opening (18a, 18b, 18c, 18d) suitable for receiving the penetration of the pins (26a, 26b) coming from the plug, the curviform head shutters being able to be pushed back towards the inside of the base against a return spring (20) by the pushing of the pins during their engagement in the opening previously closed by the said shutters and the erasure of the shutters allowing the engagement of the pins in said opening to reach the pads under tension. 5 - Connection assembly according to one of claims 1 to 4, and characterized in that the conductor wires (6, 6 ') supply allowing the connection of the plug (2) and / or the base (1) penetrate in the corresponding element with sealing means (5a, 25) ensuring the isolation of the outlet of the supply wire constituted by a cable under sheath. The plug and the base comprise locking means in their position of mutual engagement and consist of projecting lugs arranged on the plug and penetrating into receptacles of the base forming a bayonet locking device by angular rotation of the supplied plug in place in the housing provided on the receiving base. 7 - Connection assembly according to one of claims there 6 and characterized in that the openings (18a, 18b, 18c, 18d) allowing the penetration of the pins (26a, 26b) against the erasure of the valves (19) are arranged on a rotary disc (17) mounted in the bottom of the housing (15a) provided on the base (1), the disc being able to be rotated with the plug (2) in its locking movement by a bayonet device, the pins (26a, 26b) then being brought into contact with the studs (7) under tension, and the disc (17) has sealing means on its periphery coming into contact with the wall of the base and said sealing means are constituted by the peripheral wall of the disc according to a curvature bevel the disc defining a segment of sphere, said wall bearing on the frustoconical fixed wall substantially complementary to the base, the disc being pushed against this frustoconical fixed wall of support by the thrust d es flaps (19) bearing on their seats and kept under tension by their return springs (20), the support of the curved peripheral wall of the disc being made on the fixed wall tangent at any point to said curvy peripheral wall of the disk. 8- Connection assembly according to claim 7 and characterized in that the disc has four openings (18a, 18b, 18c, 18d) for the reception of four pins (26a, 26b) distributed in corresponding positions on the plug (2), the openings of the rotary disc and the corresponding pins being arranged equidistant on the disc and on the plug respectively. 9 - Connection assembly according to one of claims  7 or 8, characterized in that the rotary disc consisting of a sphere segment is mounted floating in its housing being held in abutment by its curvy peripheral wall (17a) against the frustoconical bearing wall (16) of the base, the disc being recalled in this sealed support position by the thrust of the valves (19) on springs (20) 10 - Connection assembly according to one of claims 1 to 9, and characterized in that the plug and the base comprise two members cooperating with each other and consisting of a surface unevenness on a part of the walls of the plug and of the base respectively coming into contact, these surface inequalities marking a forced passage in the final face of the blocking of the plug in its locked position by the bayonet locking assembly, this force passage thus emphasizing by the slight tactile resistance felt manually and supplemented by an audible click the arrival in the engagement position fi nal of the plug on the base and corresponding to the electrical contact between live pins and studs. 11- Connection assembly according to one of claims 1 to 10 above and further characterized in that it comprises an adapter one side of which is suitable for connection to a base or a standard plug, the other side being suitable for being connected to a bag or plug according to the invention and comprising for this purpose the complementary members.