DESCRIPTION

FIELD OF APPLICATION

The present invention relates to a zip fastener with closure with couplable profiles.

More precisely, the zip fastener according to the invention is produced using front-interlocking coupling profiles obtained mainly, though not exclusively, by extruding plastic and/or metal material or derivatives thereof.

Said profiles have a front-interlocking configuration which enables their reciprocal linear coupling for the purpose of joining, with reciprocal fastening, of two opposite strips of fabric or another material to be joined, being typically used as a closure system for items of clothing.

With the following invention it is intended to modify the fastening method of a sliding closure of a zip fastener, by bringing the point of closure from layer on layer by means of an alternating insertion, to a front closure, for opening by bending or by translation and rotation of one or two closing elements, so that the zip fastener has a sliding motion and a variable angle or a fixed angle of entry to permit the interlocking of the two elements.

The present invention is advantageously applied in the field of metalworking and mechanical engineering, small parts manufacture, stamping and moulding, fashion, textiles and leather goods, footwear, clothing and furnishings, and in general in the field of systems for closure, sliding and fastening of elements made of various materials to be joined.

The zip fastener according to the invention may also be used in the fashion and textile industries and in all applications regarding fastenings or zippers.

This does not rule out that, with appropriate modifications, both dimensional and through structural adaptations, it may be used in other fields in which the joining of two elements is required. The use of the so-called zip fastener, also called zipper, normally composed of two series of teeth, each fixed to a corresponding tape or strip or another surface, which engage with each other during closing in order to join the two parts, has long been known.

In order to obtain the opening and closing of the zip fastener, use is made of a sliding body or slider, which is made to slide along the teeth using an actuator tab or pull tab.

Inside the slider there is defined a wedge element of a shape such as to enable the engagement or disengagement of the teeth during the sliding of the slider in one direction or the other.

In particular, the slider has the function of sliding between the two parallel rows of teeth in such a way as to engage them or disengage them to obtain the closing or opening of two strips of material.

A zip fastener can further be provided, at the opposite ends of the series of teeth, with stop elements, which prevent the slider from slipping off at the beginning and end of its travel.

The actuator tab is generally permanently attached to the slider, for example by closed ring portions, provided at one end of the tab and on the back of the slider.

Over the years, the zip fastener or zipper has been proposed in many variants aimed at achieving different objectives, such as reducing the penetration of water or making the closing and opening operations more secure and faster.

By way of example, the following types of zip fasteners may be grouped together: ones with polymeric plastic teeth that are moulded, ones with polymeric plastic teeth that are sewn with thread, and ones with metal teeth, which provide for the anchorage of each single metal or metal alloy tooth using a die-casting technique or blanking technique.

Every technique for producing a zip fastener is associated with a strip of fabric called "tape", wherein at the end thereof there is a thicker zone, usually cylindrical, along the longer side, which contains additional yarn.

The tape generally consists of a polyethylene PE yarn or cotton yarn or a mix of elastomer and cotton depending on the type of zip fastener, its use and the expected aesthetic and sensory result.

From an operational viewpoint, the prior art envisages that a previously heated nylon thread is sewn with a spiral trajectory into a fabric tape with a respective beaded edge. While the sewing machine winds the pre-heated thread, sewing it, in the point farthest from the fabric tape, the sewing carriage has an abrupt movement towards the part yet to be sewn, that is, upwards, and then returns into an elliptical trajectory.

The instantaneous deformation of the trajectory enables a projection to be created on the thread, the same projection that is present in the lower part of the "metal" tooth; this projection is the part that is inserted in the correspondingly created recess, thus enabling the union of two sequential elements, identified as the main point of closure.

In the case of zip fasteners made of polymeric material, it has been possible to increase resistance to the passage of water, since each single tooth is staggered between the upper and lower part, creating a sort of "Z". By virtue of this staggering, the upper part of the next tooth rests on the lower part of the tooth below it, thereby eliminating the direct passage of water or air from one face of the zip fastener to the other.

According to patent US1219881 , there is proposed the first effective zip fastener system based on the application of a plurality of teeth, in this case metal ones, which face one another in a staggered fashion on two opposite sides of a tape, wherein said teeth determine a line of closure, being provided with a recess at the top and a projection at the bottom. The closing of said teeth is due to the sliding of a slider which is shaped so that, during passage, it will enable the divarication of the space between one tooth and another and the subsequent reciprocal interlocking interpenetration of the alternatively joined teeth.

Furthermore, according to patent US2004/0211041 , the anchorage of the tooth has been improved, making the tape and tooth system more watertight.

This solution provides for the creation of a front sheath obtained by folding on itself the final part of the strip of fabric using thick fabrics or leather that replace the beaded edge, given the similarity in the folding on itself. In this case it is envisaged that the coupling of the tooth itself on the tape is shifted, and the strip of fabric, rather than entering from the rear part of the tooth, is coupled onto the front part of the tooth and, as the excess strip of fabric is folded on itself, comes out of the upper part. There are recesses on the excess part which comes out at the front to permit the tooth to be anchored with the respective front tooth, the front strip thus taking on the form of a sheath filling the free and open spaces, which limits and in some cases prevents the passage of liquids and air.

Furthermore, according to patent TW201136547A, a tooth which, in a commercial context, will be called symmetrical is proposed. It is a tooth that is axial-symmetrical on both axes and no longer has a line of closure with an upper recess and lower projection; rather, the coupling projection is now present both at the top and bottom and the anchorage recess thereof is consequently present on both the upper and lower surfaces, with an increase in tensile strength and a nearing of the teeth no longer arranged in a "Z" configuration, but rather with an arrangement that increasingly resembles uniform rectangles, a continuous band of parallelepipeds.

According to US8146214, a zipper comprises a magnet on the initial interlocking element, and in this case the stop where the first two strips of fabric are joined, or the point in which the sliding of the fabric begins (or ends in the case of separation), becomes an "automatic" connection, i.e. without the person having to insert the strip of fabric anchored to the pin inside the reader/slider, thus beginning the joining of the two strips of fabrics.

In 2013 YKK Corporation proposed a new patent regarding "metal/alloy" zippers, proposing, for the first time, zippers that make it possible to achieve curvatures with a well-defined radius of curvature. According to this solution, the possibility of curving is given by the presence of some teeth that are not perfectly straight, but curved, and by the change in the distance of anchoring to the beaded edge between one tooth and the next tooth on the same strip of tape, acting on the spaces between tooth and tooth and between the internal and external tracks.

The large-scale use of traditional zip fasteners has brought to light several drawbacks and problems, such as those regarding the case of zip fasteners made of polymeric material, in which there always remains an opening of the slider when it comes to rest on the final stops, irrespective of whether the zip fastener is separable or not, because the chain remains open during the angling of insertion.

The problem has been partially solved by creating, using a rather laborious method, a housing that almost totally disengages the slider, thus closing the zip fastener without causing the slider to come off the two tracks.

Moreover, when a tooth of traditional zip fasteners is anchored to the tape, it is not inserted in sequence without leaving space between one tooth and another; rather, between one tooth and another there remains a space equal to the thickness of the opposite tooth, which consequently implies the need to use machines that define a distance between one tooth and another in the assembly sequence.

Should it be necessary to produce a watertight zip fastener, the traditional solutions entail having to rely on a structural change of the machine in order to apply a watertight sheath.

With traditional solutions, it has also shown to be impossible to define a maximum angle of bending of a complete zipper or of folding on itself.

Furthermore, in the case of traditional zip fasteners with a double slider, as the two sliders are brought nearer to each other during opening, one observes the formation of an opening of the zip fastener, which remains spread apart where both sliders are, at both the top and bottom.

Should it be necessary, moreover, to create an undulation of a traditional closed zip fastener, the space between one tooth and another of the same chain increases, as does the possibility of passage of any liquids/air, with all the negative consequences thereof.

Further drawbacks found with traditional zip fasteners produced according to the prior art, i.e. with alternating teeth set on two opposite sides of the tape, regard: - the need to set the spacing machine to create zip fasteners with angles;

- the noisiness of coupling polymer zip fasteners and non-smooth sliding, with consequent jerky sliding of the slider;

- a considerable difficulty in creating angles, since it is necessary to set the spacing machine and exploit the division of the elements coming from the dimensional tolerance quality control in order to secure the teeth to the beaded edge, while maintaining the slider parallel to the movement;

- a substantial passage of light upon a pulling of the two tapes in opposite directions when the zipper is closed;

- the need to use complex sliders to stop an involuntary opening movement if, when the zipper is not completely closed, one of the two strips is pulled outward;

- the possibility that the fabric of the item of clothing, or the garment the zip fastener is sewn to, will get caught or stuck due to the fact that fabric which accidentally ends up inside the reader during the opening/closing operation is trapped between one tooth and the next one, with the risk of tearing the fabric that has ended up in the slider; - the impossibility of customising with additional elements in the tooth, as occurs in some injection-moulded polymer models, where colour is the only possible customisation in metal or alloy models;

- if a colour is applied at a second stage, for example by coating, it will rapidly wear away due to the rubbing of the slider;

- the impossibility of using traditional zip fasteners in other fields of small parts manufacture, as they are not very versatile for multiple uses, even only partial ones;

- the known zip fasteners can provide little resistance if subjected to stresses of varying nature and in different orientations simultaneously; - zero resistance in the event of breakage of a single tooth or lack of anchorage between a pair of teeth;

- necessity of carrying out successive drawing steps before producing an individual tooth;

- difficulty of repair, due to the problem of exactly identifying the intermediate distance lying between two teeth in order to fix a new replacement tooth;

- the difference in design between polymer and metal production;

- the impossibility of customising a single tooth, as only the slider portion may possibly be customised.

DESCRIPTION OF THE INVENTION

The present invention aims to provide a zip fastener with sliding zips which avails itself of a plurality of coupling teeth making it possible to exploit the bending of the material in favour of a type of closure with front abutting of the teeth, thus obtaining a product capable of eliminating or at least reducing the drawbacks highlighted above.

The invention aims in particular to provide a zip fastener with a closure with front abutting and fastening couplable profiles which enables the traditional method of a sliding closure to be modified.

In particular, the invention aims to modify the traditional closure by means of a layer-on-layer system with alternating insertion into a front closure, for opening by bending or by translation and rotation of the closing elements.

This conception makes it possible to obtain a sliding of the closure elements of the zip fastener with a variable angle or a fixed angle of entry so as to permit an interlocking of the two elements, and vice-versa, in an analogous manner, the same constraint releases the elements in order to pass from a closed condition to an open one.

The closure system according to the invention makes it possible to reduce, minimise and in some cases even eliminate the passage of fluids, water and air, both between one tooth and another, understood as a progressive sequence of attachment to the tape, and between the teeth to be coupled, set facing each other.

The zip fastener according to the invention offers the possibility of defining fixed maximum or minimum rotation angles between the rest surface of a tooth and the perpendicular axis of the subsequent tooth, and to increase the tensile strength and decrease the weight of the individual component tooth, thanks to the introduction of the possibility of using a double beaded edge.

The zip fastener according to the invention further enables the mechanics of the slider to be simplified by eliminating the need for parts that stop the sliding of the slider when the pull tab is not raised, so as to prevent the zip fastener from opening by itself.

In addition, the zip fastener makes it possible to decrease the manufacturing steps necessary in traditional processes using a technique of drawing deformation and subsequent blanking for the individual tooth, as it maintains only the blanking step, without drawing, with a clear advantage from a production standpoint.

There is also envisaged the possibility of introducing a new method of producing the tooth by extrusion forming in a context of industrial production of the zip fastener according to the invention.

According to further embodiments, the zip fastener according to the invention enables the closing - sliding - sensations of the slider to be changed by adding magnetic material inside the tooth and slider. The magnets arranged with all poles identical between the tooth and slider (example: tooth - slider - tooth N|S-S|N-N|S) repel each other, creating a better sensation of slidability.

The use of a given angle of entry of the slider envisaged for the zip fastener according to the invention is conducive to eliminating the noise emitted by the teeth during their engagement.

The zip fastener according to the invention makes it possible to increase the possibility of customising the elements making up the zip fastener, both through an addition of further components, e.g. by embedding, and through the possibility of introducing processes, e.g. laser engraving or screen printing.

The zip fastener according to the invention further avoids the need to produce additional elements, besides the slider and tooth, necessary for the functioning of a zip fastener; for example, it enables stop elements or stopping points to be eliminated.

Another advantage offered by the zip fastener according to the invention consists in a reduction of the machinery necessary for the assembly and production of a zip fastener, as it decreases the number of steps necessary to form an individual tooth, thus decreasing the number of machines used and simplifying the remaining ones. In this manner, one indirectly increases the rate of production of the object, understood both as the process of moulding or stamping an individual tooth and the time of a complete cycle for the production of a zip fastener, including assembly.

The zip fastener according to the invention makes it possible to exploit a single element - a tooth of the zip fastener system - as a closure element usable individually independently of the zip fastener context; for example, a single tooth could be used with the function of a button for fabrics.

The zip fastener according to the invention makes it possible to carry out two-component or multi-material stamping or moulding for the formation of a tooth.

A new advantage offered by the zip fastener according to the invention lies in the possibility of choosing alternative polymeric or metal materials which were not used up to now because of their unsuitability for the type of features required.

A further object of the invention is the possibility of unifying the design of the zip fastener, specifically of unifying the design and the exterior appearance of the inside, using a single design both for metal/alloy models and moulded polymer products.

A further accessory that may be obtained is a slider which permits the 360° rotation of the pull tab. The rotation of the pull tab is not given by a particular geometry of the pull tab, but rather by the possibility of having an intermediate plane inside the slider which enables the pull tab to rotate by any angle.

A further advantage obtainable by the invention is the impossibility of autonomously opening the zipper if the slider has no stop. If only one of the two strips of material (fabric) making up the zipper is pulled, the zipper will not open.

The zip fastener according to the invention makes it possible to eliminate the passage of light in the middle of the zipper, the point where the teeth of the right chain are joined with the left chain.

It also makes it possible to avoid the possibility of the fabric outside the zip fastener entering into the closure and thus remaining caught, compromising the temporary functioning of the slider.

In the case of colouring of the tooth which takes place by colouring the tooth after its formation, to avoid and reduce excessive fading of the colour applied because of wear due to contact and friction between the back of the tooth and the inside of the slider.

There is also envisaged the possibility of using the zip fastener according to the invention in order to simplify any repair or replacement of a single tooth of a damaged zipper.

The zip fastener according to the invention avoids the need for a structural change, and thus for a new production process, as well as the respective machinery and costs for producing the new structure of the coupling tooth should it be necessary to introduce an accessory (sheath) designed to further decrease the passage of air/fluids.

This is obtained by means of a zip fastener with sliding zips that avails itself of a plurality of fastening teeth which make it possible to exploit the bending of the material in favour of a type of closure with front abutting of the teeth, whose features are disclosed in the main claim.

The dependent claims of the solution in question outline advantageous embodiments of the invention.

ILLUSTRATION OF THE DRAWINGS

Other features and advantages of the invention will become more apparent on reading the following description of an embodiment of the invention, provided by way of non-limiting example with the aid of the drawings illustrated in the attached figures, in which:

- figure 10 represents an overall front view of a portion of a zip fastener according to the invention;

- figure 11 is a schematic sectional view according to the lines E-E of fig. 1 , where the tape has single beaded edges on one side and double ones on the other;

- figure 12 illustrates a zip fastener according to the invention in profile;

- figure 13 represents an overall view of the zip fastener according to the invention in an axonometric projection, where the tape has single beaded edges on one side and double ones on the other;

- figure 14 is a profile view of the zip fastener according to the invention, in particular of two teeth during coupling;

- figure 15 is a view from the top side of two teeth of the zip fastener according to the invention during coupling;

- figure 16 is a schematic sectional view of a detail "A" of figure 15 of the same two teeth during coupling;

- figure 17 is a further view from the bottom side of the teeth during coupling;

- figures 18 and 19 represent schematic views of two teeth of the zip fastener according to the invention abutting each other and couplable by means of joints with a reciprocal joining of the heads;

- figures 20 to 23 represent views of the manufacturing steps for a tooth of the zip fastener starting from the extrudate with the manufacturing sequence up to the part obtained in a first version devoid of head joining elements;

- figures 24 to 31 represent views of the manufacturing steps for a tooth of the zip fastener starting from the extrudate with the manufacturing sequence up to the part obtained in a second version comprising head joining elements;

- figures 32 to 35 represent schematic views of a tooth belonging to the zip fastener according to the invention comprising seats for housing electrical or electronic elements such as wiring for LED lighting elements or the like;

figures 36 to 38 represent schematic views of a tooth belonging to the zip fastener according to the invention and usable for reciprocal button-type joining, i.e. with single couplable teeth;

figures 39 and 40 illustrate schematic views of teeth at the end of the zipper, provided with means that prevent slipping;

figures 41 and 42 represent schematic views of two sheaths according to the invention viewed from the side and front;

the views in figures 43 to 47 refer to a slider of a completely round type provided with a seat for a front-gripping hook or pull tab;

figures 48 to 54 represent a further type of a rounded slider provided with projections for an external hook or pull tab;

figure 55 represents an exploded view of a customised rounded slider produced according to the type of slider of the preceding figures 48 to

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

Making reference to the appended figures, and initially in particular to figure 10, 100 generally indicates a zip fastener according to the invention in its entirety, which comprises two strips of fabric to be joined, called tapes 101 , associated with one or more beaded edges 102 or 102'; applied on the tapes there is a sequence of teeth 103 arranged in succession on both of the tapes themselves.

The zip fastener further comprises at least one reader or slider 104 or a multiple reader according to use, which slides along the line of teeth 103 and is used to close and open the interlock between the teeth themselves, according to the type of zip fastener.

According to the invention it is in fact envisaged that the zip fastener 100 may be made in different types, including a type that is indivisible, or separable, or divisible on one side, or divisible on both sides, and, depending on the type, stops of different sizes and shapes are present, as will be seen below.

A first feature of the tooth 103 is given by the fact that is arranged together with other teeth placed consecutively on the same tape, one facing the other on the two opposite tapes, so that each of the two opposite teeth are facing each other according to a substantially symmetrical and corresponding arrangement, thus forming a front-interlocking joining element, no longer an alternatively staggered interlocking element as in traditional solutions.

In other words, the fastening between two teeth has been modified from a traditional configuration, in which the teeth are staggered, to a configuration in which every tooth positioned on the left track finds a facing, opposite corresponding tooth on the right track of the tape and vice-versa.

Moreover, compared to traditional solutions, the coupling part between two teeth has been moved from parallel to the back of the tooth to perpendicular with a front fastening, thereby avoiding the presence of spaces giving rise to problems of air and liquid tightness.

As may be seen in figures 20 to 23, which illustrate the steps of manufacturing the product in sequence, the first feature of the tooth 103 which, together with other teeth placed consecutively on the same tape and each one facing another on the two opposite tapes, constitutes the element joining the two strips to be united, is given by the fact that the teeth themselves are obtained by cutting profiles 105, which are obtained by extruding material that is preferably, but not exclusively, deformable or thermoformable, such as a synthetic, or plastic, or silicone, or metal material or derivatives thereof or the like.

In particular, the profile 105 has an elongate conformation with a substantially quadrilateral polyhedral cross section, comprising two opposite faces 106 and 107 of larger dimensions than the two smaller faces 108 and 109.

Furthermore, the two smaller opposite faces 108 and 109 of the profile

105 are provided, respectively, with seats 110 for coupling with the single beaded edge 102 and double beaded edge 102' of the tape 101 , and shaped seats consisting of alternating projections and grooves suitable for reciprocal interpenetration with the projections and grooves of the row of teeth facing them on the opposite side.

More precisely, as may be seen in figure 22, which represents a cross section of the profile 105, the seats 110 for coupling with the beaded edge 102 comprise a continuous longitudinal slit fashioned substantially in the middle of the smaller face 104 and with a positioning orthogonal thereto.

Fashioned at the bottom of said longitudinal slit, for the entire length thereof, there is an enlargement or tunnel with a substantially circular cross section which represents the aforesaid seat 1 10 into which the single beaded edge 102 or double beaded edge 102' is introduced.

In particular, during the assembly of the teeth, the tape is positioned over the slit and the single beaded edge 102 or double beaded edge 102' is introduced into the bottom tunnel-like enlargement, bringing about a perfect retention of the tooth on the tape.

At the face 109 the profile 105 takes on a particular conformation, which is the one that brings about the front coupling of the teeth 103.

In particular, again making reference to figures 20 to 23, the face 109 of the profile, if viewed in cross section, has two projections 1 11 and 1 12 in succession, alternately divided by two grooves 1 13 and 114.

In greater detail, the first projection 1 1 1 has a conformation that is curved towards the inside of the tooth defined by the curvature of the adjacent groove 1 3, and, analogously, the second projection 1 12 is curved, with a curvature having the same orientation as the first curvature, following a profile defined by the adjacent second curved groove 1 14.

Summing up, the zip fastener 100 comprises a tape 101 made in two half parts, each of which comprises respective beaded edges 102 facing a joining sector of the zip fastener; arranged on said tape there is a plurality of teeth 103 in two separate rows, likewise facing the joining sector of the tape 101 , operating between which there is a reader or slider 104 subjected to sliding along the line of the teeth 103 in such a way as to bring them from a condition of separation to one of joining or vice-versa. Said teeth 103 are divided into pairs, wherein each tooth of the same pair is connected to a respective tape, and wherein the teeth of the same pair are coupled face to face with each other during the joined condition.

Moreover, a first tooth 103 of every pair comprises at least two projections 11 1 , 1 12 facing the joining sector of the zip fastener and curved towards a first direction, alternately divided by two grooves 1 13, 114, and a second tooth 103 of the same pair comprises at least two projections 1 1 1 , 112 facing the joining sector of the zip fastener and curved towards a second direction opposite the first, alternately divided by two grooves 1 13, 114 in such a way as to achieve said joined condition through the insertion of each projection of the first tooth in the respective groove of the second tooth opposite the first.

Moreover, said projections 1 1 1 , 1 12 of the first tooth are turned towards the first direction which passes, from above to below, a plane in which the zip fastener lies and said projections 111 , 112 of the second tooth are turned towards the second direction which passes, from below to above, said plane in which the zip fastener lies, so that the two teeth of the same pair overlap each other during the joined condition.

An additional feature is given by the fact that a projection 1 1 1 projects to a greater degree than the projection 1 12 of the same tooth 103 and the opposite tooth of the same pair has a projection 112 that projects to a greater degree than the projection 1 1 1 so that each will be joined in an opposite and complementary manner relative to the other.

Furthermore, at least one projection 11 1 has a surface that is external relative to the tooth 103 and faces the joining sector and which is inclined towards the tooth itself so as to favour the slipping of the opposite tooth of the same pair.

From a construction standpoint, at least one projection 1 11 is hook shaped.

The profiles 105 and 105', obtained, as said, by extruding the deformable or thermoformable material, are cut into equally sized segments in order to obtain the teeth 103 and 103' represented in figures 23 and 27, which illustrate the product obtained after the cutting of the profiles.

Figures 20 to 23 represent a configuration wherein there are two seats 110 for housing the beaded edges, one positioned along the slit and the other on the bottom of the same. This configuration is suited to cases in which the beaded edges 102 of the tapes 101 are double, for a more secure hold.

Both the slider body and the parallelepiped slider are configured to contain electrical or electronic material.

In particular, as may be seen in figures 32 to 35, each tooth 103 or 103' is provided with seats 121 in which LED-type lighting elements or the like can be inserted, the electrical connection wiring of which is made to pass from at least one of the seats 1 0.

As said, the teeth 103 described are arranged on the respective tapes in such a way as to face each other and in particular in such a way that the curved profiles of the shaped faces 109 are arranged, as may be seen in figures 15, 16 and 17, facing one another but inverted, in such a way as to enable a corresponding and symmetrical interpenetration of the profiles with opposite faces.

As may be seen in figures 43 to 47, what brings about the front joining between the teeth facing each other is the reader or slider 104, represented in figures 43 to 47, which, similarly to traditional sliders, comprises a body having a substantially circular or rounded shape or another more suitable conformation determined also on the basis of fashion trends and aesthetic customisations, which has shaped cavities 120 that are joined together in proximity to the central part of the slider by a spreader 121.

As may be seen in figure 47, the shaped cavities 120 are arranged with an angle such as to permit two teeth to fit together and be constrained.

In particular, the shaped cavities 120 are not arranged in an exactly corresponding and symmetrical manner relative to the horizontal plane of the slider, but at least one of them has different angles.

According to one embodiment, at least one shaped cavity 120 has a position that is angled in both a transverse direction relative to the plane in which the zip fastener lies, and a parallel direction relative to the plane itself.

In other words, the shaped cavities 120 of the slider 104 have different degrees of inclination on the plane that is parallel relative to the axis of movement of the slider and on the plane that is orthogonal relative to the same axis of movement.

This makes it possible to obtain a joining between two opposite teeth by means of a progressive insertion, by rotation, of one in relation to the other.

The slider comprises extrusions and/or recesses at the top thereof to enable the application of a pulling or pushing accessory.

According to further embodiments, it is envisaged that the slider 104 is composed of a number of elements, as may be seen in figures 48 to 55. If the slider is made up of a number of elements, the presence of an upper cover 130 is envisaged, possibly comprising the extrusions 131 or recesses 132, so as to permit the addition of a pulling or pushing accessory, called a pull tab or hook.

As may be seen in the exploded view of figure 55, a further, possibly rotatable element 133 is provided, which is inserted between the body and the cover, possibly comprising projections 131 for housing said pull tab or hook.

According to further embodiments, there is envisaged a type of teeth 103' derived from further profiles 105', as may be seen in figures 24 to 31 , which are provided with projecting articulated joining elements 140 opposite the recessed grooves 141 placed on the opposite side of the same tooth and orthogonal relative to the smaller opposite faces 108 and 109 of the profile 105. These articulated joining elements 140 and 141 make it possible to rotatably connect the teeth situated consecutively adjacent on the same side of the tape, thereby obtaining better tightness against the passage of air or liquids.

Moreover, the reader or slider 104 is provided with stops comprising projections as derivations of the hook or pull tab, which are made according to a conformation such as to enable the slider to stop along only one side of the tape, and likewise to enable the joining of the two tapes 101 , rather than keeping one or both ends of the zip fastener permanently closed.

As may be seen in figures 36 to 38, a single pair of facing teeth belonging to the zip fastener according to the invention may also be used individually for a reciprocal button-type joining 122, i.e. with single couplable teeth. In this case, the strips of the button-like teeth are elongated in a complementary manner so as to define contiguous surfaces during coupling of the teeth.

Figures 39 and 40 represent an embodiment of the teeth 103 comprising a means that prevents reciprocal slipping, wherein such means comprises elongated rims 123 of at least one side of the tooth itself, which brings about the reciprocal coupling of the teeth and the reciprocal anti-slip retaining thereof.

According to further embodiments, the zip fastener according to the invention makes it possible to facilitate the operations of introducing and sliding the slider, with the addition of magnetic elements inside the tooth and of the slider. The magnets, arranged with all poles identical between the tooth and slider (example: tooth - slider - tooth N|S-S|N-N|S), repel each other, thus bringing about better slidability.

The invention has been described above with reference to a preferred embodiment thereof. However, it is clear that the invention is susceptible of numerous variants falling within the scope thereof, within the framework of technical equivalences.