1. Field of the invention
The invention concerns a variable covering device for electrical wiring conduit, in particular of the "variable angle" type for covering two adjoining ends of portions of trunking to assure the continuity of the wiring conduit at locations where it changes direction. A variable angle covering device of the invention can in particular constitute an accessory known as an "inside corner" or "outside corner" when the change of direction of the conduit occurs in different planes or as a "flat corner" when the change of direction occurs in the same plane, on the surface of a wall.
2. Description of the prior art
In electrical installations using wiring conduit employing plastics material sections, fixing a U-shape first trunking section to the wall and covering this section with another section forming a cover that clips onto the U-shape section is known in itself. Accessories must be provided to cover the end parts of successive portions. It must be possible to adapt the accessories to suit various configurations, in particular changing from one wall to another or bypassing an obstacle, or a change of direction on a wall. Two trunking portions to be joined together are generally not strictly aligned with each other or perpendicular to each other. This is why it is desirable for the covering device that caps the ends of the trunking portions to be deformable without excessive stress so that it can be fitted over the adjoining ends of the trunking portions and cover them in a relatively sealed manner.
A prior art accessory for this purpose has two portions of semi-rigid material joined together by hinge means and having respective cylindrical surfaces with a variable overlap. The two cylindrical surfaces have the hinge axis as their rotation axis, enabling angular adjustment of the two sections relative to each other. This system is costly and the overlapping surfaces must in some cases be cut away on the inside so that they do not obstruct the wiring passage.
Another prior art system also includes a hinge linking the two portions and the dimensions of their cross-sections are different so that one of the portions can partially engage inside the other one by rotation about said hinge.
Apart from their high cost, these devices are somewhat unattractive. The invention solves these problems.