Electrical connectors

A multiplug adapter comprises a casing 1 containing a stack of sliding pin carriers 6. Each carrier 6 with a pin array can be advanced to an operative position by lugs L protruding from the side of the casing. Releasable detents associated with the lugs locate the sliding carriers in the forward and retracted conditions.

DESCRIPTION 
This invention relates to a plug-in electrical connecting device having a 
plurality of pin arrays, selectable to suit the appropriate mains power 
source to the locality of use. With the appropriate pin assembly selected 
and plugged in the device provides a power socket for an appliance with a 
plug which would not otherwise be usable. Such a multi-pin device will 
hereinafter be referred to as an "adaptor". 
According to one aspect the present invention provides an adaptor 
comprising a casing, a plurality of sliding carriers each carrying an 
array of pins and slidable between a rear, pins-retracted position, and at 
least one forward, pins-protruding position, the carriers being disposed 
in stacked relationship and means for moving a selected one of the said 
carriers between the forward and rear positions. 
More specifically and in accordance with another aspect of the present 
invention an adaptor comprises a casing, a plurality of sliding carriers 
in the casing each carrying an array of pins and slidable between a rear, 
pins-retracted, position and at least one front, pins-protruding, 
position, opposed guides in the casing wall engaged by complementary parts 
on the carrier and releasable detent means operable from outside the 
casing, the arrangement being that with a carrier moved at least to a 
front position and preferably also to the rear position the detent means 
operates securely to locate the carrier in that position until the detent 
is released. 
Each sliding carrier will be conductively associated with appropriate means 
to connect the pin to the socket or other appliance connection at the rear 
of the adaptor. 
Although other forms of carrier arrays can be envisaged with the releasable 
detent means the stacked is preferred. It is further preferred that 
operating lugs or other means for the carrier should also release and 
engage the detent means. These functions can however be separated. 
In an embodiment the guides are slots extending along diametrically opposed 
positions in the walls of a tubular casing. A resiliently flexible limb 
extends from each side of a sliding carrier, each limb having an outwardly 
directed operating part to pass through the slot and being laterally 
inwardly movable against its resilience from outside the casing. The limb 
also has a projection to engage with corresponding notches on the casing 
thereby providing the detent. This arrangement can obviously be reversed 
with notches on the limb and projections on the casing. In use the 
operating parts can be used to move the sliding carrier and on arrival at 
an opposed pair of detents the limbs flex to lock the carrier. The sliding 
carrier can be disengaged from the detents by inward compression of the 
limbs against their inherent resilience.

Referring now to FIG. 1 of the drawings the adaptor illustrated comprises a 
tubular plastics casing 1 of rounded cross-section with chamfered top 
portions 2 to provide grip, and a flattened base 3. The casing has front 
and rear end covers 4 and 5. The front cover 4 has a plurality of 
apertures (a), to be described, to allow passage of pin arrays. Also well 
seen in FIG. 1 are operating lugs L to advance selectively the required 
pin arrays. These lugs will be systematically described hereinafter. At 
this stage it can be noted that there are an upper pair of lugs, an 
intermediate pair of lugs and a lower pair of lugs on opposed side walls 
and a pair of lugs on the upper and lower surfaces. Depending on the 
selective advance and retreat of a chosen lug pair a particular pin 
configuration is bought forward into an operating condition for engagement 
with a particular socket configuration. The appliance to be used can be 
plugged into socket apertures 31 at the rear of the casing. These 
apertures 31 can accept two and three pin configurations. 
Returning to the detailed description reference will initially be made to 
FIGS. 4, 5 and 6. The upper slide 6 is formed in one-piece from hard 
plastics material and comprises a bifurcated body of generally rectangular 
form from which two legs 7 extend rearwardly. Opposed inwardly directed 
shelves 40 along each casing inner side wall provide guide structure in 
which the slide moves longitudinally in in the body. A pair of contact 
pins 8 extend forwardly from the slide through slots 9 in the body front 
cover 4. The pins are of two-part construction with a flat front part 8f 
and a rear part 8r. Part 8f is in the form of a strip and part 8r in the 
form of a cylinder mounted for limited rotation about its axis. The 
forward position of the slide offers two pin configurations, with the pins 
straight for the USA in FIG. 4 and in FIG. 5 the pins rotated about the 
long axes to an inclined position for Australian and New Zealand sockets. 
An integrally formed resiliently flexible limb 11 extends forwardly and 
outwardly from each leg 7 to a laterally outwardly extending operating 
part or lug 12. Under the lug 12 is provided a detent projection 13. An 
inwardly extending stop 14 is provided to limit inward flexing of limb 11. 
The casing 1 has, at each side, an elongate rectangular slot 15 within 
which the lug 12 can be moved between front and rear positions to advance 
the pins 8. On the lower wall of each slot are provided front and rear 
detent recesses 16 and 17. 
The section A--A shown in FIG. 6 and the corresponding later section show 
the slide in divided form, one half, the right half, showing the retracted 
slide with the projection 13 engaging the slot 17 whilst on the left hand 
side the pin is shown advanced with the projection 13 engaging the recess 
16. In both front and rear position the slide is securely locked until the 
lug is depressed to free the projection 13 from the respective detent. 
Excessive inward movement of the lug is limited by abutment of the stop 14 
on the main body of the slide. The limbs 11 are deeper than the slots 15 
so that in the forward position the limbs close the slot and act as a 
safety shroud. 
FIGS. 7, 8 and 9 illustrate the intermediate pair of lugs selectively 
advancing round profile pins 18 through a wide slot 19 in front cover 4. 
In this slide and indeed in the slides described hereinafter the pins are 
effectively an electrically conductive tip and core in an electrically 
insulating body. The slide is constructed as before, and like parts are 
identified by like reference numerals. It should be noted however, that 
the slot 20 in which operating lug 21 moves is substantially greater 
length than the slot 15 and has not only front and rear detents but an 
intermediate detent 22 shown engaged in FIG. 7. The section on FIG. 9 
corresponds to FIG. 8 and shows the slide 6 advanced to the front position 
with a part to mate with the German "Shuko" type recessed socket. In the 
intermediate position with the detent projection 13 engaging the 
intermediate detent recess 22 the front of the slide 6 is flush with the 
front of the case and that is the configuration shown in FIG. 7. This is 
the configuration for other countries on the continent of Europe such as 
Spain. Differences in the guide structure in the casing for the slide 
should also be noted. Elongate guide posts 24 engage mating sockets 25 in 
the rear of the slide. 
The configuration shown in FIGS. 10 and 11 requires little comment though 
again the rear of the slide has a slightly different configuration. Again 
like reference numerals identify like parts. In principle however, the 
arrangement is similar to that described with reference to FIGS. 4 to 6. 
The pins are for Italian sockets. 
FIG. 12 and the corresponding sections in FIGS. 13 and 14 represent a 
three-pin array for U.K sockets however require more detailed description. 
The slide 25 carrying the three conductive-tipped pins 26 comprises a 
vertically disposed generally C-shaped member with limbs 27 corresponding 
to the limbs 11 of FIG. 6 with the operating lugs 28, 29 on the upper and 
lower walls of case 1 and similar detent and stop arrangements. There is 
also provided as can best be seen from FIG. 13 a basal cross-member 30 
serving as the carrier for the lower round pins, the operating limb 27 
with the lug 29 protruding from the underside of this member 30. As before 
the operation comprises resilient depression of the limbs and sliding 
engagement of the studs with the detents. 
The electrical connection arrangement to the rear socket entrances 31 (see 
FIG. 3) can be appreciated from FIGS. 15 to 17. Each conductive pin has a 
rear conductive fixing to a conductive shoe 32. On each side of the casing 
is disposed a U-shaped conductor 33, live or neutral according to the 
casing side. The shoes 32 of the upper pins engage the upper surface of 
the upper limb of conductor 33 and the bottom pair of pins the 
undersurface. Each U-shaped conductor is fastened to a bulkhead 34 by a 
conductive pin 38 (FIG. 17) passing through the bulkhead to a resiliently 
flexible conductive channel 35 constituting a socket member. As can best 
be seen from FIGS. 17 and 15 bulkhead 34 forms part of transversely 
extending wall structure 37 extending across the rear of the interior of 
casing 1. This structure not only houses socket channels 35 but also 
provides a guide and back stop for the rear of the slides. 
Means can be provided for connecting the upper flat pin of the British type 
arrangement to the rear earth socket. In the absence of such connection 
the pin 26 will be made of insulating plastic. A movable safety shutter 36 
(see FIG. 16) is provided inside rear cover 5. This shutter, under spring 
bias covers entrances 31 until pushed aside by an entering plug. 
In an alternative construction the slides 5, 7, 8 and 10 are formed for 
sliding interengagement with one another. As a further modification the 
rear of the casing may include a voltage converter/transformer with 
control means on the casing exterior. The adapter can thus deal with 
different voltage values in a power supply. 
In the device, as described above, the possibility exists for two or more 
slides to be advanced together. This is undesirable from the standpoint of 
safety and it is proposed to incorporate some means such as a rotatable 
shutter which obstructs the forward sliding of all but a selected slide. 
As an alternative the terminal tips may be of electrically insulating 
material.