The subject of this invention is a box of a roller shutter, furnished with a hinge facilitating its front wall closing and/or opening.

The roller shutter box, known from the European Patent Nº EP 0 841 460 B1, is furnished with a closing set comprised of the profiled seat of a S-shaped cross-section, with a Z-shaped catch set inside the seat, being a closing of the bottom part of the box.

The embodiment of this invention is the construction of a box of a roller shutter furnished with a hinge that facilitate closing and/or opening of the bottom part of the box wall, practically self-acting or requiring application of an insignificant force only, whereas the joint of the components making the hinge structure is practically invisible from the outside of the box front wall, whereas the hinge seat is placed in the upper part of the box and, due to its shape, covers a part of the side cover, effecting the top part of the box is fixed in its proper position.

According to this invention, the box of a roller shutter fixed at its ends to the side covers, consisting of two parts, is characterised by that its top part has a seat for a catch of the bottom part of the box, formed of two half-round components of different curve radii, making together with the half-round component ended with the inserting stop the slot of a width slightly greater than the catch thickness. The catch, installed inside the seat slot, has the ending positioned above the centre of the curvature of the half-round component. The centre of the half-round component curvature is situated at the angle "α" amounting to 35° up to 40° in relation to the plane running through the symmetry axis of the round part of the side cover.

The advantage of the box of a roller shutter, according to this invention, is a relatively simple structure of the seat and/or the catch making the hinge, providing a wide angle of opening and practically self-automatic closing of the front part of the casing, or closing it applying only an insignificant force, as well as it constructs a small slot visible from the outside of the front part of the box, which improves its aesthetic quality.

The subject of this invention is shown in the drawings; in the Fig. 1, the end fragment of the box of a roller shutter furnished with the side cover is shown in an axonometric view; in the Fig. 2, the front view of the inside of the box of a roller shutter is shown; and in the Fig. 3, the magnified view of the hinge constructed of the seat and the catch is shown.

As it is shown in the drawing, the box 1 of a roller shutter is fixed, at its ends, into side covers 2, and consists of two parts 3 and 4. The top part 3 of the box 1 has a seat 5 for the catch 6 of its bottom part 4 constructed of two half-rounded components 7, 8, of different curve radii, which together with the half-round component 9 tipped with the inserting stop 10 they both make the slot 11 of a width slightly greater than the thickness of the catch 6. The catch 6, placed inside the slot 11 of the seat 5, has its tip 12 situated at a height above the centre of curvature 13 of the half-round component 7. The centre of curvature 13 of the half-round component 7 is positioned at the angle α amounting to 35° up to 40° in relation to the plane 14 running through the symmetry axis of the round part 15 of the side cover 2, and encloses a part of the edge of the side cover 2.