Multiple Pin Electrical Plug

This invention relates to a multiple pin electrical plug. Such a plug has a variety of pin combinations of varying geometry, able to accept the several voltage outlet supplies of the major countries of the world.

According to the present invention there is provided a multiple pin electrical plug from which pins are able to extend in a number of configurations dictated by the movement of a shutter plate having a slider that is movable to at least the same number of discrete positions, as said number of configurations.

In one multiple pin electrical plug a pin slide is arranged to co-operate with the shutter plate to an extend, or retract, position and to an extend but non-retractable position.

The invention will be more fully understood from the following description given by way of example only with reference to the several figures of the accompanying drawings in which:

FIGS. 1A, 1B, 1C are presented in third angle orthographic projection. FIG 1A shows an inlet voltage face of a multiple plug, FIG. 1B a side elevation and FIG. 1C an outlet voltage face.

FIG. 2.sub.1 shows the inlet face of FIG. 1A with an alternative inlet configuration different from that of FIG. 1 but in an intermediary condition.

FIG. 2.sub.1A shows to an enlarged scale in oblique perspective the configuration of FIG. 2.sub.1.

FIG. 2.sub.1B also in oblique perspective shows the pin configuration in its final form for one of the electrical usages.

FIG. 3 is another alternative inlet configuration shown in a form similar to that of FIGS. 1 and 2.

Referring now specifically to the figures. In FIGS. 1A, 1B, 1C a unitary plug shown generally at 10 has either an inlet face F of area abcd or abef depending on whether ancillary electrical means is to be combined with the plug (see our co-pending United Kingdom application No. 8201337). The unitary plug for convenience only is shown with a two part case 11a, 11b of inlet area a b e f held together by screws 11.sub.1 and 11.sub.4. The case has outlet sockets 12.sub.1 12.sub.2 and vent louvers 13. (In the smaller plug abcd two screws 11.sub.5, 11.sub.6 will be inserted or sealed by other means).

Consider now the multiple pin plug shown generally at 20 (FIG. 1A). A movable shutter plate 21 has an integral slider 22 accessible to the hand of the operator, the edge 22.sub.1 of the slider may be brought into alignment with index marks on the inlet face such as marks A, B.sub.1, B.sub.2 and C to give four separate pin geometries.

In FIG. 1A the edge 22.sub.1 is against index mark A and the flat pin pair P1, P2 may be withdrawn and oriented (turned through an angle) where they are held in correct orientation for use in accepting the electrical voltage outlets of United States of America and Australasia for example. This is a first pin geometry.

Consider now the position shown in FIG. 2.sub.1. The edge 22.sub.1 of slider 22 is agaist index mark B1 and the pin pair, P3 P4 may be each withdrawn and rotated on their individual pin axes to engage a locking structure whereby they are locked and the pins used in this position. This is a second pin geometry.

Consider now the position shown in FIGS. 2.sub.1, and 2.sub.1A. The edge 22.sub.1 of slider 22 is again at index mark B.sub.1 FIGS. 2.sub.1, 2.sub.1A) and slider plate 21 allows pin-slide 23 of general rectangular prismatic form to be withdrawn out of inlet face F and to be functionally positioned for use. The pin-slide 23 has integral side rails 23.sub.1, 23.sub.2, 23.sub.3, 23.sub.4 that coact with opposed plate protuberances 21A, 21B (FIG. 2.sub.1). With the pin-slide 23 extended (FIG. 2.sub.1B) the right cylindrical pin-pair P3, P4 is locked by rotation of each pin individually as described above and the shutter plate 21 moved so that edge 22.sub.1 is in alignment with index mark B.sub.2 (FIG. 2.sub.1B). This brings opposed plate protuberances 21A, 21B, 21C and another one (hidden and thus not shown) respectively behind the pin slide rails 23.sub.2, 23.sub.4, 23.sub.1, 23.sub.3. This is shown for co-operating parts 21.sub.A, 23.sub.2, 21.sub.C and 23.sub.1 in FIG. 2.sub.1B (co-operating parts 21.sub.B, 23.sub.4, 21.sub.D and 23.sub.3 are not visible). The shutter plate 21 is provided with a protuberance 21E (well seen in FIG. 2.sub.1B) that with the plate on index B2 brings the edge of protuberance 21E against face 23.sub.5 of pin-slide 23 and gives to it an enhanced stability in electrical usage. Clearly at index mark position B2, pin-pair P3, P4 in pin-slide 23 cannot be retracted to re-enter the plug until protuberances 21A, 21B, 21C, and the hidden one are again raised for edge 22.sub.1 to come on to index mark B1 when the pin-slide 23 is retractable.

The pin-pair P3, P4 with pin slide 23 extended as shown in FIG. 2.sub.1B is for use with the recessed electrical voltage outlet sockets to be found in Germany, Belgium and other parts of Europe, for example such as the Schuko socket. In some such sockets an earth pin from the socket can enter the plug inlet over surface 23.sub.5. This is a third pin geometry.

In FIG. 3 the shutter plate 21 is with edge 22.sub.1 at indes C and the three heavy rectangular section pins P5, P6, P7 can come out beyond the inlet face F and cooperate with a locking structure whereby each can be rotated through a right angle to lock the pin. These pins are for use with the voltage outlets to be found inter alia in the United Kingdom, pin P5 being an earth pin oriented one right angle out of alignment with live and neutral pins P6, P7. This is a fourth pin geometry.