Electrical connector having pressure contacts

An electrical connector having a socket provided with pressure contacts. A plug is provided which is at least partially inserted in the socket. The connector is provided with a latching mechanism formed of a hook provided on the plug or socket which engages a spur provided on the socket or plug, respectively, when the plug is inserted in the socket. Either the socket or the plug, or both, are provided with at least one hump which projects from an interior surface of the plug or an exterior surface of the socket.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to an electrical connector having pressure contacts 
and more particularly to an improvement for such an electrical connector. 
2. Discussion of Background and Relevant Information 
The electrical connectors of this type comprise a socket provided with 
pressure contacts provided, for example, with a braid surrounded by a 
spring, as mentioned in French Patent 2,365,872 in the name of Applicant, 
or constituted by rocker elements as in French patent 2,422,270, or French 
patent 2,531,577 and its certificate of addition, likewise in the name of 
the same applicant, and a plug adapted to be inserted at least partially 
in the socket. 
By virtue of the pressure exerted by the contacts and also that exerted by 
an ejection spring generally provided between the plug and the socket, so 
as to allow for a quick break (to avoid in particular the electric arc of 
breaking the circuit, etc.), it is necessary that the plug be retained in 
the socket by a latching means. 
The latching means mentioned above is generally constituted by a hook 
provided on the socket and which is adapted to be in contact with a spur 
provided on the plug. 
The hook is generally rockable by means of a pressure button. 
These connectors may or may not comprise one or two safety discs, as 
disclosed, for example in French patents 2,212,655 and 2,270,696, in the 
name of the same applicant. 
The insertion of connectors provided with at least one safety disc 
generally occurs in three steps: a pre-insertion axial movement, a 
rotation to align the respective contacts (the one or more discs thus 
undergoing this rotation), and a second axial pressure, until latching. 
The proper angular position of the plug and of the socket at the beginning 
of the maneuvers, as well as the translational and rotational guidance, 
are assured, for example, by a bayonet type system. 
The connectors can, if desired, also comprise a sealing joint positioned 
between a portion of the plug and a portion of the socket. 
It is desirable to provide only a single hook, so as to be able to allow 
for a sudden break of the current by relying upon it to free it, the 
contact springs and the ejection spring assuring the said break by sudden 
spacing of the plug and of the socket, the said plug being however, 
prevented from separating completely by the guidance means provided, as 
explained above (previously cited bayonet system, for example). In effect, 
a plurality of hooks would require a delicate manipulation if one desires 
that they be all freed in a synchronous manner so as to obtain the 
previously mentioned sudden break. 
Under the effect of the pressure exerted, as explained above, by the 
contacts and by the ejection spring, the plug rests on the latching hook. 
It results necessarily that the plug is biased to turn around its 
retention point in a plane passing through its longitudinal axis and 
through the hook. In addition to a poor aesthetic appearance, the 
misalignment of the plug and of the socket plays a negative role, 
particularly on the efficacity of the contacts achieved (misalignment of 
the contacts of the plug with respect to those of socket), on the wear of 
the conductive braids, and on the sealing which can only be weakened by 
nonuniform crushing of the joint. 
The solutions to this problem have been sought and studied for a long time. 
To completely eliminate the above disadvantages, it has in particular been 
envisioned to multiply the number of latching means. Thus, certain 
electrical connectors comprise four hooks, or two hooks (with an insertion 
ring and/or bayonet system). 
However, although these solutions may be appropriate for certain 
applications, they eliminate the advantage of having a single hook, as 
explained above. 
This is why it has appeared until today, that the presence of a single hook 
necessarily had to be associated with the disadvantage of axial 
misalignment of the plug and of the socket. Given this situation, the 
research has been directed to two improvements: the limitation of 
inclination and the adaptation of this inclination. 
To limit the inclination, it has been attempted to adjust, as best as 
possible, the diameters of the plug and of the socket, as well as the 
dimensions of the guidance means. However, it is clear that the tolerances 
of manufacturers resist the total elimination of a certain play between 
the plug and the socket. 
With a view to adapting to the inclination, one positions the socket on a 
vertical wall, taking care preferably, that the hook be positioned 
upwardly, in a manner such that the weight of the cable connecting the 
plug makes it possible to compensate at least in part the said 
inclination. 
With respect to the sealing, it has also been imagined to provide a joint 
which is thicker and/or has a lip and/or further has a nonconstant cross 
section. 
Finally, one has also worked on the aesthetic aspects, by providing a 
rounding or an inclination of the surface of the socket, on the side of 
the plug. 
It is clear that all of the means of limitation or adaptation mentioned 
above are gimmicks that do not resolve the question. 
SUMMARY OF THE INVENTION 
The inventor has in particular achieved in overcoming the prejudgment that 
a single hook necessarily caused inclination. 
The electrical connector conceived by the inventor to resolve the problem 
posed is remarkable in that the plug and/or the socket comprises one hump 
which projects slightly with respect to the exterior surface of the plug 
or respectively, interior to the socket. 
Preferably, the one or more humps of the socket and/or the plug are 
positioned in a plane passing through the longitudinal axis of the plug 
and of the socket and substantially through the latching means. 
There exists a plurality of embodiments which are possible. According to 
one of the embodiments, the one or at least one of the humps of the plug 
is provided to the posterior portion thereof which is embedded in the 
socket and on the side of the latching means. 
According to another embodiment, the one or at least one of the humps of 
the plug is provided towards the anterior portion which embeds in the 
socket and on the side diametrically opposed with respect to the latching 
means.

Plug 1 is provided with contact pins such as 3a, 3b, 3c and the socket with 
opposing contacts such as 4a, 4b, 4c. 
The number and arrangement of the pins 3a-3c and of contacts 4a-4c depend 
obviously on the nature of the current to be transmitted. It is clear, 
also, as the drawings show, that the contacts 4a-4c are pressure end 
contacts constituted in a conventional manner by a conductor braid, a 
contact head, and a helicoidal spring surrounding the said braid, each 
contact being positioned in an appropriate housing in an insulated block 5 
of socket 2. 
As was said above, the plug and the socket are provided with means for 
guiding the insertion and means for retention (not shown) such as bayonet 
systems, for example. Furthermore, the socket and/or the plug can, of 
course, comprise one or more safety discs adapted to mask before insertion 
the contacts of the socket and/or the pins of the plug. Likewise, an 
ejection spring is in general provided for the reasons stated above. 
However, so as to simplify the drawings, the connector according to the 
invention comprises only a minimum number of elements, it being 
understood, furthermore, that the invention applies also to this 
particularly simplified type. 
The socket 2 comprises furthermore a hook 6, which is pivotably mounted 
around the axis 7 and which is adapted to be placed in contact with a spur 
8 provided on the plug, as seen in the drawings (see particularly FIGS. 5 
and 6). 
A hook 6 is biased in the position shown in the drawings by a compression 
spring 9 while a press button 10 forming a lever allows by simple pressure 
to pivot the hook 6 against the bias of said compression spring 9. 
Furthermore, socket 2 is generally adapted to be in part embedded in a 
vertical wall and in this case, the hook 6 is then generally positioned 
upwardly on the (top of the socket). 
Bearing 11 shown in the drawings is adapted to receive in a journalled 
fashion, a cover which is biased to closure by an appropriate spring and 
which is adapted to cover in a conventional manner the socket in rest. 
The plug is furthermore provided with a joint 12 adapted to tighten on a 
front edge 13 of the socket at the end of the insertion maneuvers, as will 
be explained below (FIGS. 5 and 6). 
FIG. 1 illustrates a plug 1 provided with two humps, 111 and 112, which 
project towards the exterior (for a better marking with respect to the 
humps, the hundreths number shows the number of the figure and the tenths 
number is the reference of the plug or respectively, of the socket on 
which it is provided). These two humps are provided in a plane passing 
through the longitudinal axis of the plug and of the socket and 
substantially through the latching means 6 and 8. This arrangement is 
furthermore utilized in the other embodiments shown. 
However, the hump 111 is provided, as is shown in FIG. 1, towards the 
posterior portion of the plug which must be embedded in the socket and on 
the side of the spur 8, while the hump 112 is on the contrary provided 
toward the anterior portion and on the side diametrically opposed to the 
spur 8. 
FIG. 2 shows an embodiment wherein the plug comprises only a single hump 
211 of the type 111 in FIG. 1. 
In FIG. 3, the plug also comprises a hump 311 of the same type as 111 and 
211, but here the socket 2 is provided with an interior hump 321 provided 
towards the posterior portion in which is inserted the plug and on the 
side diametrically opposite to the hook. 
In FIG. 4, only the socket is provided with humps 421 and 422, the later 
being equivalent to the hump 321 in FIG. 3, while the hump 421 is provided 
towards the anterior portion in which is inserted the plug and on the side 
of hook 6. 
In fact, there exist a large number of possible embodiments. If one limits 
oneself to the preferred positions such as 111, 211, 311 (at the posterior 
and side spur) and 112 (anterior and opposite) for the plug and 421 
(anterior and side hook), 321, 422 (posterior and opposite side) for the 
socket, certain possible and preferred embodiments are not shown. It is 
thus, for example, that the plug 1 of the FIG. 1 can comprise only hump 
112, while socket 2, still in FIG. 1, can in this case comprise or not 
comprise a hump of the type 421 (FIG. 4). Likewise, for a plug 1 like that 
of FIG. 4 (without hump), socket 2 could have only one of humps 421 and 
422. 
However, to facilitate the insertion, it appears preferable that the hump 
of the plug be arranged as shown at 111, 211 and 311, while a hump of 
socket 2 will preferably be of the type 321 or 422, such that the 
embodiments of FIG. 2 and FIG. 3 are particularly advantageous. 
In effect, the embodiment to FIG. 3 provides an easy introduction of the 
plug (hump at the posterior portion of the plug and a good equilibrium 
(hump opposite hump in the socket), while the embodiment of FIG. 2 is 
particularly simple, by offering furthermore the advantage of a plug which 
can be utilized with the previously existing sockets. 
The insertion maneuvers depend on the guidance means provided which 
require, for example, a first translation, a rotation, and a final 
translation. In a particularly simple system, it is possible to imagine 
only an axial pressure and one then passes from FIGS. 1 and 2 to FIGS. 5 
and 6, respectively. 
It is clear that at the end of their extent, hook 6, which pivots first 
towards the exterior (by virtue of its shape) under the effect of spur 8 
and against the bias of spring 9, then latches the assembly by folding to 
the rear of the said spur 8 under the effect of spring 9. An unlatching is 
easily obtained by pressing on button 10. 
As FIGS. 5 and 6 show, the plug and the socket are perfectly coaxial and 
the joint 12 is crushed uniformly between the plug and the socket 
(otherwise stated, the surfaces facing the plug at the socket are 
perfectly parallel) and this, by virtue of the humps such as 111, 112 and 
211. 
Although FIGS. 5 and 6 illustrate more particularly the embodiments of 
FIGS. 1 and 2 after insertion, one can well imagine equivalent figures for 
embodiments of FIGS. 2, 3 and 4, as well as for the other embodiments not 
shown but mentioned above. 
As can also be seen in the figures, the humps can have a slight bevel, at 
least on their attack edge, in a manner as so to facilitate insertion. 
Finally, it is clear that each hump can be obtained directly by molding in 
the form on an applied appendage. The nature and the material of the humps 
depend, of course, on the material constituting the surfaces of the hump 
and of the socket on which they are provided, which can be metallic or 
synthetic. 
It is clear, as previously stated, that the invention relates to a 
plurality of types of connectors, with or without sealing joint, with any 
number of contacts, etc.