This invention relates to electrical connectors.
Electrical connectors have been proposed in which a tab comprising a circular opening is arranged to be force-fitted over a projection provided on the female portion of a connector (referred to herein as clip) thus providing a locking arrangement. This form of engagement has two disadvantages: on the one hand, the pressure to be exerted on the male and female parts should be sufficiently great to ensure that the female part is deformed until locking takes place, and this sometimes makes assembly difficult; on the other hand, it often happens that the deformation of the female clip is such that it remains to some extent permanent, with the result that accidental disconnection can occur. Moreover, in order to effect disconnection a tool has to be inserted into the clip to deform it again, and this aggravates the deformation of the clip accordingly.
According to the present invention we provide an electrical connecting device comprising a male tab, a female clip having a complementarily-shaped body in the general form of a hollow parallelepiped, open at one end to receive the said male tab and defining relatively an upper Wall and a lower or bottom wall, and an insulating cap into which the female clip is received, wherein said upper wall is formed as a resilient electrical contact for the male tab and the bottom wall is slotted to define - 3 side edges providing supporting surfaces for the male tab and a resilient tongue between said edges attached to the body at its rear end, said tongue lying generally in the plane of the bottom wall, having a catch arranged at an intermediate portion along its length and being shaped to engage in an orifice of corresponding form in the male tab, and further having a free front end extending generally towards the said open end of the body and a front leading end bent outwards relative to the body through an angle of about 45°, and wherein the cap consists of a sleeve of complementary shape to that of the clip capable of sliding along said clip, said sleeve comprising on its bottom wall an abutment having a sloping shoulder whose edge engages in an inclined plane with the inclined front edge of the tongue of the clip when the two parts are assembled in order to cause the tongue to bend elastically downwards by engagement of the tongue with the shoulder when withdrawing the male tab from the female clip, thus disengaging the catch from the orifice of the male tab.
In order that the invention may be more fully understood an embodiment in accordance therewith will now be described, with reference to the accompanying drawings, in which:Figure 1: a view from below of a female clip portion of an electrical connector; ' Figure 2: a side elevation, in partial section, along line B-B in Figure 4, of the clip shown in Figure 1; Figure 3: a plan view, from above, of the clip shown in Figures 1 and 2; Figure 4: an end view of the clip shown in Figures 1 to 3; S0500 - 4 Figure 5: a section on the broken line A-A in Figure 2; Figure 6: a partial longitudinal sectional view of a standardised male tab; Figure 7: a side elevation in longitudinal section through an insulating cap intended to cover the connection and facilitate the disconnection thereof; Figure 8: a plan sectional view of Figure 7.
Referring initially to Figure 6 this shows part of the male portion of the connector which comprises a flat rectangular tab 1 having a central opening 2. This tab is fixed in known manner to the conducting portion of a conductor by a set-in eyelet and to the insulator surrounding this conductor by a clamp fitted on to this insulator.
Such a male tab is of known kind, with standard ised dimensions.
Figures 2 to 5 inclusive show the female clip 3 portion of the connector which has the general form of a hollow rectangular parallelepiped, for the reception of tab 1.
Clip 3 comprises, an eyelet 3a intended to be fitted over a conductor and a clamp 3b for fitting on to an insulator.
The lower wall of the parallelepiped portion has a generally U-shaped cutout portion 4 defining there· within a central tongue 5, as well as two side edges 6 and a front edge 7. Being held only at one end, the tongue 5 is elastically deformable, whilst the edges 6 and 7 are fixed. The front end portion 5a of the tongue is set downwardly at substantially 45° to the remaining portion of the tube when in an unstressed condition and, sosoo behind the portion where the front end portion 5a meets the remaining portion of the tongue there is provided a substantially circular cutout 8 having a slightly smaller radius than that of the orifice 2 in the tab 1.
The material of the tongue 5 located inside the cutout 8 is inclined slightly upwards to form a semicircular catch 9 which projects into the interior of the clip 3.
Preferably, a small tab 10 is cut out inside the tongue 5 and is also inclined downwards in the opposite direction to the tip 5a of the tongue 5.
Thus, it is apparent that if downward traction is exerted either on the tip 5a or on the tongue, the entire tongue 5 is elastically depressed.
The top wall of the parallelepiped comprises two symmetrical portions 11 which meet along a line. The side walls 13 connect the portions 11 to the fixed edges of the bottom wall. Thus, the parallelepiped may be formed from; a metal sheet in one piece which is bent back on itself twice so as to comprise: a bottom wall formed by the edges 6 and 7, and the tongue 5 (bottom wall connected to the eyelet 3a and clamp 3b); two side walls 13; and a top wall, made up of two symmetrical portions 11 which abut on one another along the line 12. The two portions 11 forming the top wall are concavely curved at their central portions 11a.
The method of operation of the connecting device thus described is as follows. The male tab 1 is inserted in the clip 3 via the orifice 14 (Figure 2) of the hollow parallelepiped. The portions Ila of the upper wall consisting of two portions 11 press this tab 1 downwards and this tab 1 presses against the catch 9 of the tongue 5, thus causing the latter to be elastically depressed downwards. When the orifice 2 is above the catch 9, the latter penetrates into the orifice 2 and the tongue 5 straightens - 6 up again. The male tab 1 is then elastically clamped between the curved walls Ila and the bottom wall of the clip 3 consisting of the fixed edges 6 and 7 and the movable tongue 5; it is locked in position by the catch 9 which projects into the orifice 2, with the result that accidental disconnection is resisted.
In order to disengage the tab 1, it is merely necessary to exert downward traction on the tongue 5 either by means of the tip 5a or using the small tab 10 so as to free the catch 9 from the orifice 2.
This downward traction is effected by means of a special insulating cap shown in Figures 7 and 8.
The cap shown in these figures is a parallelepipedinal sleeve 15 made of a relatively flexible elect15 rically insulating material, such as rubber, which is threaded on to the clip 3 as shown by broken lines in Figure 2.
The top wall of the sleeve 15 has a projection 16 lockingly engageable with the sleeve 15 in the vicinity of the eyelet 3a and the bottom wall comprises an abutment 17 where inclined wall face 17a has a gradient corresponding to or slightly greater than that of the tip 5a (50°, for example), this abutment 17 extending over the entire width of the bottom wall of the sleeve 15.
It will be seen that, if the sleeve 15 is slid towards the back of the clip 3, the inclined plane 17a engages on the tip 5a and forces the tongue to move downwards, thus freeing the tab 1 from the catch 9. Thus, the sleeve 15 acts both as an insulating cap for the connection and a control means for disconnection.