In waterproof zips of the prior art it is possible for water to get in through the zip in the area of the abovementioned tapes adjacent to the end of the zip even after the zip has been closed by the above- described slider. This is due to the fact that there are inevitably gaps between the tapes, the slider and the last pair of teeth joined by it, and although these gaps are very small, water is nonetheless able to get in through them.

This drawback obviously defeats the whole object of a waterproof zip, which is to stop water getting in at any point.

The inventor of the present innovation has therefore devised what is as far as he is aware a novel type of waterproof zip that eliminates the problem described above.

The zip of the invention is provided with a slider divided into at least two parts, one on each side of the zip, which are able to move axially with respect to each other at right angles to the plane of the zip.

By bringing them together in the direction indicated above, using means mounted on the slider itself, the regions of the two tapes in the area adjacent to the said end of the zip are clamped together, compressing them so that water cannot get in between them and the slider.

This is made possible in part by the fact that two recesses are formed in the two adjoining tapes so that, when brought together, they form an opening complementary in shape to a member perpendicular to the zip and projecting from one of the parts of the slider, which can move in a hole formed in the other part to allow the abovementioned relative movement between the two parts.

In order to make certain that no water can get in at all, according to the invention the said two tapes are also made, in the area of the tapes situated beyond the closing end of the zip, in a single piece, or in two pieces hermetically welded together.

The subject of the present invention is therefore a waterproof zip as disclosed in the appended Claim 1.

A more detailed description will now be given of two preferred embodiments of the waterproof zip of the invention, with reference also to the appended drawings, which show: in Fig. 1 an exploded perspective view of the said illustrative embodiment of the waterproof zip of the invention with some hidden parts drawn as if visible; in Fig. 2 a partly sectioned side view of the zip seen in Fig. 1, taken along the plane of longitudinal symmetry of the slider, perpendicular to the plane of the zip, in the situation in which the said tapes are clamped between its said two parts; and in Fig. 3 a perspective view of another illustrative embodiment in which the said tapes are clamped between two discs brought together and containing the slider inside them.

Referring to the abovementioned Figures 1 and 2, these show a waterproof zip 1 according to the invention

comprising two rows of teeth 2,3 attached to the adjoining edges of two tapes 4,5 of plastic material, and a slide 6 which, as it moves in either direction, joins and separates the said two rows of teeth 2,3 by known methods in such a way that the zip 1 is closed when the slider 6 reaches the end lt of the zip 1.

Unlike zips made in accordance with the prior art, however, the said slider 6 comprises a first part 6m and a second part 6n on opposite sides of the plane ß of the zip 1 and able to move with respect to each other at right angles to the said plane This movement is possible because a member consisting of a shaped pin 10 projects perpendicularly from the second part 6n and fits moveably inside a hole 9 in the first part 6m. The relative movement of the first part 6m with respect to the second 6n is brought about by rotating a U-shaped piece 7 whose intermediate side 7t is fixed to the fist part 6m in such a way that it rotate, and which has two projecting portions 14i having a cross section in the form of an eccentric cam.

It should be observed that, in order to attach the said U-piece 7 and its fixing parts, it is advantageous to attach over the top of the slider a third part 6p which, after assembly in the U-piece 7, can form a single whole with the said second part 6n, to which it can be bonded or welded or preferably fastened by small screws.

A fork 8 is attached to the first part 6m in such a way that it can move parallel to the plane ß of the zip and insert its tines 8r, 8s into corresponding recesses (for which see Fig. 2) formed in the second part 6n, when the two parts 6m, 6n have been brought together by the U-piece 7.

This fork 8 makes it possible to keep the slider 6 with its two parts 6m, 6n together after closing the zip 1

and after clamping (as described below) the tapes 4,5 between these parts.

The clamping referred to above, which as mentioned earlier ensures that the zip 1 of the invention is truly waterproof, is brought about by the two parts 6m, 6n of the slider when brought together by the said U- piece 7 and achieves the described result of a hermetic seal because of the fact that, in the zones Z3, Z4 (Fig. 1) of the said two tapes 4,5 adjacent to the end lt of the zip 1, there are two recesses 11,12 which, when the tapes 4,5 are brought together to close the zip, form an opening 13 into which the said shaped pin 10 fits with a complementary fit with at least its front part lOf or more preferably, as illustrated, with its entire cross section.

It should be pointed out that the pin 10 is shaped with, for example, an elliptical cross section as in Fig. 1, to prevent relative rotation between the two parts 6m, 6n of the slider 6.

It can be seen from the drawings that at the end lt of the zip 1, the points where water could get in are limited to the line around the said opening 13 which follows the perimeter of the cross section of the shaped pin 10, but this outline keeps within a relatively large area surrounding it, in which the corresponding zones Z3, Z4 of the tapes 4,5 are pressed forcibly against each other by the two parts 6m, 6n of the slider 6.

It should be observed that, in order to achieve the hermetic seal described above, the zones Zl, Z2 of the two tapes 4,5 situated beyond the end lt of the zip 1 must have no points of discontinuity: for this purpose, in order to ensure that the adjoining regions 4e, 5e of the tapes 4,5 are not for example brought together along a line L that separates them (the line in

question is shown in dashes in Fig. 1), they must be welded together along this line or, in a still more advantageous solution provided by the inventor, they may be formed by cutting them along a line to which the rows of teeth 2,3 are to be attached, but which ends in the said opening 13, so that the two tapes form a single unbroken whole in the said zones Z1, Z2 lying beyond the end lt of the zip 1.

Another embodiment 101 of the waterproof zip according to the invention can be made by modifying the shape-and arrangement of the parts: it is possible for example to add a first disc 102, as shown in Fig. 3, underneath the slider 103, moveably connected to a second disc 104 above it via a rod 105. Moving the second disc 104 towards the first 102 by means of a rotating member 106 with cams, of the type already described in respect of the previous illustrative embodiment, has the effect that the discs, with the slide 103 inside, clamped between their edges 102d, 104d the said two adjoining regions of the zip tapes (not shown), thus achieving the same result as explained earlier of making the zip truly waterproof.