FR2498383A1 - Mains socket with protection against electrocution - has spring biased connecting plate moved by plug only so that plug is live only when completely inserted - Google Patents

Abstract

The electrical socket comprises a box (1), a cover with holes for a male plug (4) and a connecting plate (15) which is moved, by the plug only, from the cover towards the back (5) of the socket. This connecting plate (15) has holes in order to permit the insertion of the plug pins (4a) into plug contacts and has conductive pins (16a,16b) which are shifted in relation to its holes. When a plug (4) is inserted, the pins (16a,16b) of the connecting plate (15) enter the terminals (18a,18b) situated on the back of the socket. A spring (22) pushes the connecting plate (15) onto the cover of the socket. In this socket, each terminal (18a or 18b) on the back is formed from two parts; one is connected to the electrical source and the other to one of the plug contacts.

Description

Electric shock-proof electrical outlet
The present invention relates to an electric shockproof electrical outlet.

More specifically, it is aimed at improvements to electrical anti-electrocution sockets of the kind described in French patent NO 77/39232 and in its Certificates of Addition NO 78/16340 and 78/34279 filed in the name of Applicant.

French Patent NO 77/39232 relates to an electric shockproof electrical outlet remarkable in that it comprises - a hollow body or insulating housing; - An insulating cover constituting the front wall of said housing and which is crossed by holes allowing the passage of the conductive pins of a Maltese plug which are, for example intended to be inserted into conductive sockets engaged in said holes; - an insulating connection pallet mounted inside said casing with a capacity for displacement parallel to the axes of said holes and comprising recesses facing the latter, said insulating connection pallet carrying connection members offset relative to said axes of the holes allowing the passage of said pins ;; - Means ensuring the return and the maintenance of said connection pallet near said front wall when no plug has been engaged in the socket; - A bottom wall carrying contacts placed opposite the connection members and which are separated from them when said connection pallet occupies a position close to said front wall; - connection means such as, for example, terminals for connection to the conductors of the supply network, for connecting said contacts to a source of electric current; - And an arrangement or means by which it is possible to move said connection pallet in the direction of said bottom wall when the pins of a male plug are engaged in the female socket, so as to achieve the junction of said organs of connection and said contacts,
In the 1st Addition Certificate NO 78/16340, an improved embodiment of the socket outlet according to the invention has been described, according to which the retraction of the connection plate is obtained under the push of the pins of the plug. male which in particular made it possible to extend the scope of the invention to modern electrical sockets, without significant modification of the general structure of the latter.

On the other hand, in the 2nd Certificate of Addition N 78/34279, an improved embodiment of the anti-electrocution socket is exposed, according to which the latter is provided with locking means preventing the recoil of the connection pallet other than by the introduction of a male plug with an adequate body into said socket.

The anti-electrocution electrical outlet manufactured in application of the French Patent and the two above-mentioned Certificates of Addition, offers absolute security against the risk of electrocution, in particular with regard to children who may be tempted to introduce their fingers or metallic objects in the conductive sockets of said socket, as has been well explained in said Patents and Certificates of Addition.

The only criticism that lton was able to make against the anti-electrocution electric outlet described in Patent NO 77/39232 and its two Certificates of Addition NO 78/16340 and NO 78/34279; is that it is more complex to manufacture and has a higher cost price than those of ordinary sockets without protection, which, in the end, should not be considered as a real inconventent compared to the advantage vital it provides and which alone should be taken into account for obvious security reasons.

The relative complexity of the different embodiments of the electric shock socket described in the Patent and the two above-mentioned Certificates of Addition stems, in particular, from the fact that the conductive sockets and the connection members are connected by means of conductors flexible electrical, which implies, for each of these, the provision of two connection terminals, as well as the fact that the locking means preventing the recoil of the connection pallet require a particular construction of the socket or its box cover, and the use of a determined type of male plug to obtain the unlocking of said means.

The purpose of this patent is therefore more specifically to simplify the electrical anti-electrocution outlet described in
Patent and the two Certificates of Addition above, allowing to achieve a less expensive realization, without however reducing the security offered by said socket.

This objective is achieved by means of an embodiment according to which the contacts installed in the bottom of the socket of the socket and intended to receive the conductive pins of the mobile connection pallet, are constituted by sockets or clamps comprising, each , two spaced blades or jaws, one of which is electrically connected to one of the plug connection means and the other of which is electrically connected to one of the plug contacts placed on the pins driving path a male plug, inside said shoemaker, so that the introduction of the latter into said socket causes the connection pallet to move back towards said bottom and the establishment of an electrical connection between the blades or m cholres connected to the connection means such as connection terminals, and the blades or jaws connected to the plug contacts, by means of the pins of said connection pallet.

According to another characteristic, the anterior portions of the plug contacts arranged on the penetration path of the pins of a male plug have a capacity for radial movement towards the outside and are provided with locking members placed on the path. backward movement of the connection pallet, so that the insertion of a male plug into the socket causes the plug contacts to separate and unlock the connection pallet which can be pushed back towards the bottom of the latter, preferably by means of said pins of the plug.

According to another characteristic, the recesses or orifices presented by the connection pallet opposite the household holes in the front wall of the socket for the passage of the pins of the plug, have a diameter or a width, in at least one direction, smaller than the outside diameter of said pins.

 Thanks to this embodiment, the electric anti-electrocution electrical outlet according to the present invention only comprises a very small number of simple additional members compared to ordinary electrical outlets, so that its manufacture is not hardly more complicated and expensive than that of the latter.

On the other hand, the implementation of the invention does not entail any significant change in the general design of modern plugs provided with a grounding pin, so that the plug manufactured under this patent can adopt the common commercial forms, standardized or not.

Finally, and this remains the most important, the electrical outlet according to the present invention provides absolute security and eliminates any danger of electrocution due to the introduction of fingers or metallic conductive objects into the holes of the outlet.

These aims, characteristics and advantages, and others still, will emerge more clearly from the description which follows and from the accompanying drawings in which
Figure 1 is an exploded perspective view of an exemplary embodiment of the electrical outlet anti-electrocution according to the invention.

Figure 2 is an axial sectional view passing through the insertion holes of the pins of a plug, said socket being shown in neutral position and installed in a recessed box.

FIG. 3 is an axial section along line 3 - 3 of FIG. 2.

Figure 4 is a view similar to Figure 2, showing the taking in the conduction position resulting from the introduction of a plug.

FIG. 5 is an axial section along the line 5 - 5 in FIG. 4.

Figure 6 is a rear view, on a larger scale, of the mobile connection plate.

Figure 7 is a plan view, on a larger scale, of the socket, after removal of the front wall or cover and the connection plate.

Figure 8 is a detail view, on an even enlarged scale, illustrating the operation of the claimed anti-electrocution socket.

FIG. 9 is a perspective view of one of the plug contacts of the socket.

Reference is made to said drawings to describe an advantageous, although in no way limitative, embodiment of the electrical anti-electrocution socket outlet provided with the improvements targeted by the present invention.

This socket comprises, in a manner known per se, a hollow body or case 1, of parallelepipedal shape or the like, which can be made of molded insulating material. The front wall 2 of this box is provided with holes 3a, 3b intended to authorize the passage of pins 4a, 4b of a male plug 4 bipolar or other, while the bottom or rear wall 5 of said housing carries the terminals 6a, 6b allowing the connection of the conductors of the supply network.

At least one of the walls 2 and 5 of the socket is removable, the second of said walls being able to be molded in one piece with the body 1.

According to the example illustrated, the front wall 2 is removably attached to the front face of the body 1 and thus constitutes a cover which may be in one piece or in the form of several separable elements placed side by side.

According to the embodiment shown, the front wall or cover 2 comprises a base 2a fixed to the body 1, for example by means of a central screw 7, and a cover cap 2b disposed against the front face of said base and detachably secured thereto, for example by means of elastic locking tabs 2c.

 The base 2a is provided with holes 3a, 3b which open into the central opening 2d presented by the cover 2b, the front face of which comprises a flange 2e of a shape corresponding to that of said opening and serving to center the body of the male plug. .

The socket can advantageously be arranged so that it can be installed in an external box 8 intended to be built into a wall or a partition.

To this end, it is then provided, in a known manner, with studs 9 rocking under the action of screwing or unscrewing screws 10 carried by the base 2a and accessible on the front face of the latter.

When the socket is provided with a grounding pin intended to be inserted in the earthing socket 4c of the male plugs, this pin 12 is fixed on the base 2a and its rear end is electrically connected, by example by means of a conductive plate 12a embedded in the thickness of said base, to a nut 13 also embedded in the latter and in which is screwed the threaded end of the central screw 7 holding the cover 2 against the front face of the shoemaker 1.

 The posterior end of the screw 7 passes through a central orifice 5a formed in the bottom 5 of the socket and is in contact with a terminal 14 fixed on the rear face of said bottom, by the operating head 7a of said screw which is produced in a conductive material. This terminal is intended for the connection of the earth wire outlet and is therefore connected to the pin 12 by means of the screw 7, the nut 13 and the plate 12a.

In the hollow body or housing 1, is housed a connection pallet 15 executed in an insulating material and mounted with the ability to move parallel to the axes x-x and x'-x 'of the holes 3a, 3b.

This axially movable connection pallet carries connection members 16a, 16b oriented towards the rear and positioned offset with respect to the axes x-x and x'-x 'of the holes 3a, 3b.

These connection members are, interestingly, constituted by conductive pins of quadrangular section, preferably rectangular, arranged parallel to the axis of the socket and whose axes yy and y'-y 'are offset by 90 relative to the axes xx and x'-x '.

The connection pallet has recesses 17a, 17b arranged opposite or in alignment with the holes 3a, 3b and, according to a characteristic of the present invention, these recesses 17a, 17b have a diameter or a width, in at least one direction , less than the outside diameter of pins 4a, 4b of the mayor plugs.

The pins 16a, 16b carried by the connection pallet are intended to engage, by translation, when the said pallet is pushed backwards through the pins of a male plug, into fixed supply contacts 18a, 18b installed in the bottom of the socket box, opposite said pins 16a, 16b, on the axes yy and y '-y1, respectively.

According to the present invention, the supply contacts 18a, 18b are constituted by sockets or clamps each comprising two blades or space jaws 19, 20.

The blade or jaw 19 of the socket or clamp 18a is electrically connected to the terminal 6a for connection to one of the conductors of the supply network, while the blade or jaw 19 of the socket or clamp 18b is electrically connected at terminal 6b.

On the other hand, the blade or jaw 20 of the sockets or clamps 18a is electrically connected to one of the plug contacts 21a, 21b placed on the driving path of the pins of a male plug.

These plug contacts 21a, 21b have an elongated shape and are arranged in a direction substantially parallel to the axis of the socket.

They are advantageously constituted by a U-shaped blade made of a conductive material and endowed with a certain elastic bending capacity.

Each plug contact thus comprises two branches substantially pa alleles 21c, 21d whose free ends are oriented towards the front wall of the socket and arranged at a short distance from the latter and whose posterior integral ends are embedded in the bottom or wall rear 5 of the body or case of said socket or positioned in housings formed in said bottom.

The blade or jaw 20 of the sockets or clamps 18a, 18b can advantageously be made in one piece with one of the branches of the plug contacts 21a, 21b, and, for example, with the outer branch 21c of the latter, said blade forming, for example, in this case, an angle of 90. with the lower part of said branch.

The connection pallet 15 is provided with slots 15a for the passage of the inner branch 21d of the plug contacts, 21a, 21b and lateral notches 15b for the passage of the outer branch 21c of said contacts. On the other hand, it comprises a central orifice 15c through which the screw 7 passes. It is conceivable that said connection pallet is thus perfectly guided, during its movements forwards or backwards, by the branches of the plug contacts and by the central screw 7.

A compression spring 22 mounted around said central screw ensures the retention and return of the connection pallet in the advanced position according to which the pins 16a, 16b carried by said movable pallet are sufficiently distant from the blades or jaws 19, 20 of the sockets or fixed clamps 18a, 18b, so that no electrical connection is possible between said blades. The spring 22 is wedged, by its opposite ends, on the one hand, against the bottom 5 of the body or housing 1 and, on the other hand, against the rear of the movable pallet 15 which advantageously comprises a small central centering sleeve 15d for said spring.

According to another characteristic of the present invention, the anterior portions of the plug contacts arranged on the driving path of the pins of the plugs, have a capacity for radial movement towards the outside and are provided with retractable locking members. placed on the recoil path of the connection pallet.

According to the illustrated embodiment, these locking members are constituted by lugs 21e directed inwards which is provided with the external elastic branch 21c of the plug contacts 21a, 21b, these neutralization lugs being, for example, obtained by cutting and folding of symmetrical lateral tabs, a short distance from the free end of said outer branch.

In the "neutral" position, the connection pallet 15 is pressed on the locking pins 21e, by its rear face and, more precisely, by the surfaces delimiting the longitudinal edge of the notches 15b opening laterally.

In this position, the gap formed between the front portions of the external branches 21c of the plug contacts 21a, 21b has a dimension less than the distance between the external faces of the pins of the male plugs intended to cooperate with the socket. In this way, the introduction of a male floche in said socket, causes the spacing of said branches which are pushed back towards the outside, the inner branches 21d being wedged by the internal edge of the slots 15'a.

It is well understood the operation of the electrical outlet anti-electrocution according to the present invention.

In the neutral position (Figures 2 and 3), the movable pallet 15 carrying the connection pins '16a,' 16b is held forward by the spring 22 and locked in this position by the neutralizing members 21e.

In this situation, the pins 16a, 16b are remote from the sockets or clamps 18a, 18b whose spaced blades or jaws are not connected by any conductive member, so that the plug contacts 21a, 21b are not in circuit or "under voltage "and can be safely touched. However, the anterior ends of the plug contacts 21a, 21b being arranged at a distance from the holes 3a, 3b of the front wall 2 of the socket, no conductive member can be touched with the fingers, however small they may be.

On the other hand, if a child were to introduce conductive rods such as nails, pins, wire, etc., in the orifices of the socket, the latter would freely pass through the recesses 17a, 17b of the pallet. connection, without moving the latter backwards.

Under these conditions, these rods which would abut, at the end of the race, against the insulating bottom 5 of the body or case of the socket, not being in contact with any live member of the latter, could not transmit any dangerous electric discharge to the 'child. In addition, if these rods were bent, they would abut on the upper face of the insulating connection pallet locked by the neutralizing members 21e preventing its recoil other than by the introduction of a male plug.

When a male plug 4 is inserted into the socket, the pins 4a, 4b of said plug ensure, successively, on the one hand, the spacing of the outer branches 21c of the plug contacts 21a, 21b (traced in fine broken lines from FIG. 8) and, consequently, the unlocking of the connection pallet 15, then, on the other hand, the retraction of said connection pallet in the direction of the bottom 5, which leads to the introduction of pins 16a, 16b of the latter in the supply contacts 18a> 18b. The blades or jaws 19, 20 of the supply contacts being electrically connected by pins 16a, 16b, an electrical connection is thus established between the connection terminals 6a, 6b and the plug contacts 21a, 21b which are thus energized.

The withdrawal of the plug ("aie causes a reverse movement of the connection pallet which is biased forward under the action of the spring 22, which has the effect of isolating the plug contacts 21a, 21b, as soon as the pins 16a, 16b are no longer in contact with the sockets 18a, 18b.

It can also be observed that the retraction of the connection pallet and the switching on of the plug contacts takes place only when the pins of the malt plug are inserted over almost their entire length in the socket, the few millimeters remaining at this moment cannot be achieved with the fingers, given the weakness of the distance remaining between the facing faces of said plug and socket, even in the absence of a protective collar on the front face of the latter.

Likewise, when the plug is removed from the socket, the plug contacts are switched off, as soon as the pins of said plug are removed over a few millimeters, well before they can be touched with the fingers.

It is also emphasized that the sleeve 15d with which the connection pallet is provided can also fulfill the role of a locking member, because, in the event of tilting of said pallet, said sleeve being no longer exactly coaxial with the screw or rod 7 tends to hang on the latter which may have an abutment shoulder for said sleeve.

Claims (10)

R E V E N D i C'A T i O N S 1. - Electric anti-electrocution socket outlet comprising - a hollow body or housing (1) - a front wall or cover (2) through which holes (3a, 3b) are intended to allow the passage of the conductive pins (4a, 4b ) a male plug (4); - an insulating connection pallet (15) mounted inside said housing with the ability to move parallel to the axes (xx, x'-x ') of the holes (3a, 3b) of the front wall and carrying members or pins connection (1xi, 16b) including the axes (yy, y '-y'). are offset from the axes (x-x, x'-xt) -said holes; - Means (22) ensuring the recall and maintenance of this connection pallet towards the front, when no male plug is engaged in the socket; - a bottom wall or bottom (5) carrying fixed supply contacts (18a, 18b) arranged opposite the connection members or pins (16a, 16blet which are spaced therefrom when no male plug is engaged in the socket; - connection means (6a, 6b) such as, for example, connection terminals to the conductors of the supply network, for connecting said supply contacts to a source of electric current; - and a arrangement or means (4a, 4b and 17a, 17b) by means of which it is possible to move said connection pallet in the direction of said bottom wall when a male plug is inserted into the socket, so as to achieve the junction of said connection pins and said power contacts ;; characterized in that said power contacts (18a, 18b) are constituted by sockets or clamps each comprising two spaced blades or jaws (19, 20), one of which ( 19) is electrically connected to one of the braking means (6a, 6b), and the other (20) of which is electrically connected to one of the plug contacts (21a, 21b) placed on the insertion path of the pins of a male plug, to the inside said body or case. 2. - electrical outlet anti-electrocution according to claim 1, characterized in that the anterior portions of the plug contacts arranged on the driving path of the pins of a male plug, have a capacity of radial movement in the direction of outside and are provided with locking members (21st) placed on the recoil path of the connection pallet. 3. - electrical outlet anti-electrocution according to one of claims 1 or 2, the movable connection pallet (15) is provided with recesses or orifices (17a, 17b) arranged opposite or in the alignment of the holes (3a, 3b) of the front wall (2), characterized in that said orifices or recesses have a diameter or a width, in at least one direction, of dimension smaller than the outside diameter of the pins (4a, 4b) male plugs. 4, - Electric anti-electrocution socket outlet according to any one of claims i to 3, characterized in that the plug contacts (21a, 21b) are each made up of a U-shaped blade and have two branches substantially parêllêles (21c, 21d) whose free ends are oriented towards the front wall of said socket and spaced from said wall, and whose rear posterior ends are embedded in the bottom or rear wall (5) of the body or case (1) or positioned in housings formed in said bottom. 5. - electrical outlet anti-electrocution according to claim 4, characterized in that the neutralization members (21e) are carried by the outer branch (21c) of the plug contacts (21a, 21b), said neutralization members being , for example, constituted by lugs formed by symmetrical cut and folded lateral tabs. 6. - electrical outlet anti-electrocution according to any one of claims 1 to 5, characterized in that the connection pallet (15) has lateral notches (15b) for the passage of the plug contacts (21a, 21b ) or for the passage of the outer branch (21c) thereof. 7. - electrical outlet anti-electrocution according to one of claims 4 or 5, characterized in that the inner branches (21d) of the plug contacts (21a, 21b) pass through slots (15a) that includes the pallet connection (15). 8. - electrical outlet anti-electrocution according to claim 1, characterized in that the connection pins (16a. 16b) have a quadrangular section, preferably rectangular. 9. - electrical outlet anti-electrocution according to any one of claims 1, 2, 4, 5 and 6, characterized in that the plug contacts are executed in a material with a certain elastic bending capacity. 10. - electrical outlet anti-electrocution according to claim 1, characterized in that the connection pallet (15) has a central orifice (15c) and a central sleeve (15d) has in the extension of the latter, said orifice and sleeve being traversed by a rod or screw (7) which allows, for example, the removable fixing of the front wall (2) on the front face of the housing (1) and the establishment of a connection between a plug pin earth (12) carried by said front wall and a terminal (14) intended for the connection of the earth wire and disposed at the rear of said housing.