Device for mechanical and electrical assembly of miniature molded cases

#The invention relates to a device for assembling two adjacent molded cases housing miniature electrical switchgear having a circuit, notably a control circuit, connected to two external connection terminals, comprising a fast-fixing connecting runner which in the active position overlaps the interface of the two cases, and whose parts protruding on both sides of said interface are each secured to one of the cases to mechanically assemble the two cases.

#An assembly device of the kind mentioned, described in U.S. Pat. No. 4,591,228, enabled a modular low voltage miniature electrical switchgear system to be achieved. The switchgear generally comprises control circuits or auxiliary circuits which have to be interconnected when two or more modules are assembled. In the simplest example of a two-pole remote-controlled switch achieved by assembly of two single-pole remote-controlled switches, the two operating coils must be connected in parallel to ensure simultaneous operation of the two controls. This paralleling can be achieved at the level of the external connection terminals of the control circuit, but fitting of these connections complicates assembly.

#The object of the present invention is to improve the above-mentioned mechanical assembly device, by associating with it the electrical connection function of the circuits, notably the control circuit of the assembled cases.

#Other advantages and features will become more clearly apparent from the following description of an illustrative embodiment of the invention, given as a non-restrictive example only and represented in the accompanying drawings in which:

#FIG. 1 is a schematic perspective view of two modules or cases assembled by the device according to the invention.

#FIG. 2 is a partial view of FIG. 1, the assembly runner being assumed to have been removed.

#In FIGS. 1 and 2, modules or units, for instance miniature molded cases 10,11 of remote-controlled switches, are adjoined and assembled to form a multipole unit. Each molded case 10,11 is clipped in the usual manner by its rear face 12 onto a symmetrical profile support rail (not shown). The front face 13 of the cases 10,11 is fitted with a manual operating handle 14 of the remote-controlled switch. Power connection terminals 15 are arranged on the narrow side faces 16,17, whereas the successive cases 10,11 are adjoined by their large side faces. On these narrow side faces 16,17 there are also arranged external connection terminals 18 located above and set back from the power terminals 15. On each of these narrow side faces 16,17, a slide 19 is in addition provided, which extends above the external connection terminals 18, in a manner perpendicular to the large faces of the case over its whole width. In the slide 19 a dove-tail shaped runner 20 is slidingly mounted. The two ends 21,22 of the runner 20 are shaped as hooks able to clip onto conjugate protrusions 23,24 arranged on the bottom of the slide 19. In the assembled position represented in FIG. 1, the runner 20 overlaps the interface between the two cases 10,11 and its end hooks 21,22 are clipped onto the conjugate protrusions 23,24 of the cases 10,11 to keep the latter assembled. Each case 10,11 is supplied with its runners 20 in the central position in the slide 19, and after the two cases 10,11 have been adjoined, the runner is moved in the direction of the other case to the overlapping and assembled position, represented in FIG. 1, the slopes of the protrusions 23,24 and hooks 21,22 being arranged to achieve clipping together in this overlapping position. An assembly device of this kind by sliding runners 20 is described in detail in U.S. Pat. No. 4,591,228, which should advantageously be referred to for further details.

#According to the present invention, the runner 20 bears on its face internal to the slide 19 a flexible metal blade 25 forming an electrical contact bridge extending in the sliding direction of the runner 20. In the bottom 26 of the slide 19 there is arranged a contact pad 27 designed to cooperate with the contact bridge 25. The contact pad 27 is formed by an end of a connecting strip 28, whose other end 29 is inserted in an external connection terminal 18. The contact pad 27 is housed in a groove 30 with limited opening, arranged in the bottom of the slide 19 to prevent any accidental contact.

#Referring more particularly to FIG. 8, it can be seen that a runner 20 in the assembled position of two cases 10,11 provides an electrical connection between the contact pads 27 of these two modules. The electrical connection via the contact bridge 25 between the two cases 10 and 11 is established at the same time as their mechanical assembly by the runner 20. FIG. 8 shows on the left-hand part a runner 20 in the inactive position and it can easily be seen that by sliding it to the right, it is possible to assemble the case corresponding to case 11 while also providing the electrical connection.