Method for producing a fastening device and product obtained with said method

Abstract: A method for producing a fastening device (1) and the product obtained with the method. The method includes the simultaneous production of at least two elements (6,7) that constitute the device; the elements are mutually linked by a flexible connecting element (5).

Description: The present invention relates to a method for producing a fastening device and to the product obtained with said method. Fastening devices are used, for example, in sports shoes such as ski boots, roller skates, ice skates, or mountain boots, and are generally constituted by levers having a plurality of separate interconnected elements cooperating with each other to join the flaps of the shoe. Italian Utility Model Patent No. 182322 discloses a closure device that comprises a lever element that is pivoted, at one end, at one of the flaps to be fastened, the end of a traction element being articulated to a median portion of the element, the traction element being provided with a hook member at the other end. The hook member can be coupled in an engagement seat provided at the other flap of the shoe to be fastened. The traction element has means for adjusting its useful length and at least one substantially flexible portion. The elements that constitute the device are all made of aluminum or might be made of plastics, according to the requirements linked to the shoe on which they are used. If the elements are made of aluminum, they are obtained by stamping adapted plates; this step is followed by other treatments adapted to complete each individual element according to desired aesthetic and mechanical requirements. If some elements must be made of plastics, they are obtained by means of injection molds. As in the previous case, the various elements, once they have been obtained by molding, can be subjected to further working to complete them from the mechanical or aesthetic point of view. In any case, regardless of whether the components are made of plastics or of aluminum, they must be mutually assembled by using additional elements, such as for example pins wherever it is necessary to obtain a rotation or connecting elements such as protrusions, snap-together seats, or others. Essentially, conventional fastening devices, particularly for sports shoes, are all composed of a plurality of separate structural elements with the addition of further elements that are required to achieve the mutual connection of the first ones. This conventional method has considerable drawbacks: it entails producing the individual parts, then finishing them aesthetically and structurally, and assembling the various parts together with a sequence of operating steps, most of which are manual. Furthermore, each step requires a certain time and accordingly contributes to increase the overall costs of the device. The aim of the present invention is therefore to solve the described technical problems, eliminating the drawbacks of the cited prior art by providing a method that allows to produce fastening devices, such as for example levers for sports shoes, with a low cost and in a short time. Within the scope of this aim, an important object is to reduce the number of components that constitute the fastening device. Another important object is to provide a method that allows to reduce the number of machines required for the treatments for producing the fastening device. Another important object is to provide a method that allows to reduce the treatment steps required to obtain the fastening device in a configuration that is complete and therefore ready to be assembled to the shoe. Another important object is to provide a method that allows to obtain a fastening device that can be stored more easily and is very easy to install on shoes. Another important object is to provide a method that allows to obtain a product that has very low production costs. Another object is to provide a method that allows to obtain a product, such as a fastening device for sports shoes, that is reliable and safe in use, has low manufacturing costs, and allows to achieve optimum adaptability to the particular region in which it is placed on the shoe. In accordance with the invention, there is provided a method for producing a fastening device, and a fastening device itself, as defined in the appended claims. Further characteristics and advantages of the invention will become apparent from the detailed description of a particular but not exclusive embodiment, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a schematic side view of the producing line for the method according to the invention; figure 2 is a schematic view of the device obtained after the injection-molding step; figure 3 is a sectional side view of the device; figures 4 and 5 are views of the device associated with the flaps of a shoe, in the closed condition and in an intermediate closure condition; figure 6 is a top view of the device in the condition shown in figure 4; figure 7 is a lateral perspective view of the device in the position of figure 4; figures 8 and 9 are side views of the device according to further embodiments. With reference to the above figures, the method for producing a fastening device, designated by the reference numeral 1, comprises a first injection-molding step, performed by means of a mold 2 that is constituted by an upper part 3 and a lower part 4, wherein adapted seats are provided for forming the fastening device 1 after the injection step. Said first injection-molding step occurs at a flexible connecting element, such as a tape or cable 5, that is inserted at the mold 2. The first injection-molding step produces at least two elements that constitute the fastening device 1; to this purpose, the accompanying drawings illustrate further embodiments, which entail for example the production of a lever arm 6, of a traction element 7, and optionally of a support 8 for the articulation of the lever arm 6, said support 8 having means for locking to a first flap 9 of a shoe. The lever arm 6 is overlap injection-molded on the tape or cable 5, and the traction element 7 is also overlap injection-molded, at an adapted distance, on the tape or cable 7. Optionally, on the opposite side with respect to said traction element it is possible to overlap injection-mold the support 8, as shown in figure 3. Advantageously, the lever arm 6 has, at the surface 10 that is directed away from the first flap 9 during closure of the device, an axial recess 11 that is adapted to constitute a seat for the tape or cable 5 during the closure of the device, as shown in figures 4 and 7. The traction element 7 has, at the end that is opposite to the one connected to the lever arm 6 by means of the tape or cable 5, temporary engagement means that are constituted by a curved protrusion 12 that interacts with complementarily shaped grip means that are associated with the second flap 13 of the shoe. The grip means are constituted for example by a tooth 15 that is rigidly coupled to, and protrudes from, the second flap 13, or by a rack 14 as shown in figure 8, or by a tooth 15 that is obtained monolithically from the flap 13, as in figure 9. The support 8 has, on the opposite side with respect to the first flap 9, two curved shoulders 16 that allow the resting and rotation of two wings 17 that protrude parallel to each other from the lever arm 6 toward the traction element 7. On the opposite side with respect to the pair of shoulders 16, the support 8 has means for locking to the first flap 9; said means are constituted by a tab 18 on which an annular recess 19 is provided; the recess acts as a seat for the detachable engagement of said first flap 9. After the first injection-molding step, the method entails a second step for blanking the ends of the flexible connecting element 5 that protrude from the traction element 7 and from the support 8 away from the lever arm 6. The second step occurs by means of an adapted blanking tool 20 and allows to obtain the finished device, ready for use. The device can be advantageously stored in adapted removable containers. As an alternative, after the first injection-molding step the tape or cable 5 that comprises the elements of the fastening device can be wound at an adapted reel 22 for subsequent use during the assembly of the product on which the device is to be applied. Likewise, the tape or flexible cable 5 can be unwound from a similar reel 22 before the first injection step. The method allows to produce a fastening device in which the components are mutually linked by the flexible connecting element, which allows an operator to easily and quickly assemble it to the flaps of a shoe and, by means of an adapted spacing between the lever arm 6, the traction element 7, and optionally the support 8, to achieve rotation for the lever arm 6 and thus fasten the flaps. It has thus been seen in practice that the method allows to eliminate most of the connecting elements of a conventional fastening device, at the same time reducing the production steps required to obtain the complete device and thus also reducing the number of machines required for the treatments. Furthermore, storage has also been improved and simplified, in view of the extremely easy assembly of the fastening device; the components that constitute the fastening device are in fact mutually linked by the connecting element; it also allows the operator to further simplify the operation for assembly to the shoe. Finally, the low number of machines that are used, the reduced number of production steps, and the extremely easy and simple assembly allow to considerably reduce the production cost of the fastening device. Furthermore, the flexible connection between the lever arm and the traction element improves the adaptability of the fastening device to positioning on the shoe and the ability to absorb any impacts without inducing deformations or breakages in the components of said device. The method and the fastening device according to the invention are of course susceptible of numerous modifications and variations, all of which are within the scope of the appended claims. The materials and the dimensions that constitute the individual components of the device may of course also be the most pertinent according to the specific requirements. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims: Method for producing a fastening device for coupling a pair of flaps (9,13) of a shoe, comprising the simultaneous production of at least a lever arm (6) and a traction element (7) that constitute said device (1), said lever arm (6) and said traction element (7) being mutually linked by a flexible connecting element (5). Method according to claim 1, characterized in that it comprises a first step for the injection-molding, on said flexible connecting element (5), of at least said lever arm (6) and said traction element (7) that constitute said device (1). Method according to claim 2, characterized in that it comprises a second step of blanking said flexible connecting element (5); on which said lever arm (6) and said traction element (7) that constitute said device have been injection-molded, and a subsequent storage step in removable containers. Method according to claim 2, characterized in that it comprises, after said first step, the storage of said device by winding on an adapted reel (22) said flexible connecting element (5), which comprises said at least two elements (6,7) that constitute said device (1). Method according to claim 2, characterized in that it comprises, prior to said first step, the unwinding of said flexible connecting element from a reel (22). Method according to claim 1, characterized in that a lever arm (6) and a traction element (7) are injection-molded to overlap on a cable (5). Method according to claim 1, characterized in that a support (8) is injection-molded to overlap on a cable (5). Fastening device for coupling a pair of flaps (9,13) of a shoe, comprising at least a lever arm (6) and a traction element (7) characterised in that said lever arm (6) and said traction element (7) are fabricated on, and mutually linked by, a flexible connecting element (5). Device according to claim 8, characterized in that said connecting element is constituted by a tape or a cable (5). Device according to one or more of the preceding claims 8-9, characterized in that said lever arm (6) and said traction element (7) are injection-molded on said connecting element (5). Device according to claim 8, characterized in that on said connecting element (5) there is further fabricated a support (8) for the articulation of said lever arm (6) that has means for locking to one of the flaps (9) of a shoe. Device according to claim 11, characterized in that said support (8) has, on the opposite side with respect to said flap, a curved end (16) that allows the resting and rotation of one end of said lever arm (6). Device according to claim 12, characterized in that it comprises means for locking to one of the flaps (9) of a shoe constituted by a tab (18), which protrudes on the opposite side with respect to said curved end (16) and on which there is an annular recess (19) that acts as a detachable engagement seat for said flap. Device according to claim 13, characterized in that said lever arm (6) has, on a surface (10) that is directed away from said flap (9), an axial recess (11) that acts as a seat for said cable (5) during the closure of said device. Device according to claim 14, characterized in that said traction element (7) has, at an end that lies opposite to the one connected to said lever arm (6), means for temporary engagement with complementarily shaped grip means (15) that are associated with said other flap of the shoe to be joined.

Inventors: GORZA ROBERTO, GORZA, ROBERTO
Applicants: BENETTON SPA, BENETTON GROUP S.P.A.
Application year: 1996
Main classification: B29C45
IPC codes: A43C11, A43B5, B29C45