Studded shoe

Abstract: The present invention relates to a shoe, in particular a sports shoe or walking boot, which has an outer sole (10) and at least one stud (20) which is releasably connected thereto and interacts with the ground when the shoe is used. According to the invention, the at least one stud (20) comprises a stud-fastening mechanism (100), and the outer sole or outsole (10) has at least one locking recess (50). Furthermore, according to the invention, the stud-fastening mechanism (100) can be moved into a position in which it engages behind the locking recess (50) in order to produce the releasable connection between stud (20) and sole (10). Advantageously, the fastening mechanism (100) comprises at least one locking hook (110) which is arranged in an essentially pivotable or displaceable manner in a cavity (40) in the interior of the stud.

Description: 1. Field of the invention The present invention relates to shoes, in particular sports shoes or walking boots, the outsole of which is provided with exchangeable studs. The present invention relates in particular to a stud-fastening mechanism which is preferably used for elongate studs. 2. Prior art It is known in the prior art to provide sports shoes or walking boots, and in particular football boots, with studs, in order to increase the grip of the shoe, in particular on soft ground such as for example grass. The term "studs" is to be understood in the context of the present invention as meaning all possible elements which are arranged on outsoles of shoes in order to increase grip. The term "studs" is therefore intended to include conventional studs for football boots, but also, for example, spikes as are used, for example, for sprinting boots on cinder tracks, as well as studs for walking boots. Only conventional football boots are described in the following description of the prior art and the invention; however, it is pointed out that the intention is also to encompass all possible types of studs in the above sense. The use of studs on football boots has long been known. The studs used originally formed an integral part of a football boot outsole, which is usually made from plastic. However, this had the drawback that the studs were quickly worn down in particular as a result of running on hard surfaces, such as for example asphalt, resulting in the need to replace the entire shoe when the wear reached a critical level. Furthermore, it was not possible to use studs which had been adapted to changeable ground conditions or to adapt the shape and length of the studs to the individual needs of a player. If the ground conditions changed, and therefore the studs were unsuitable, it was necessary to use a new pair of boots with correspondingly adapted studs. Studded boots which had been adapted to the particular requirements were expensive custom-made articles. For this reason, studded shoes provided with exchangeable studs have long been offered. It was easy to provide exchangeable studs in the case of the studs of round cross section or with rotational symmetry which were conventionally used. The stud - now usually made of metal - was simply screwed on to the outsole by means of a screw thread. With this known technique, it was possible, by using self-tightening screws, to ensure that the screw connection between sole and stud did not become detached. However, for some time the prior art has been moving away from the use of round or rotationally symmetrical studs, since these studs were no longer able to satisfy current requirements with regard to optimum grip when quickly changing direction and sprinting. Therefore, nowadays it is preferred to use elongate studs which have been optimized for the individual types of sport in terms of their shape and their orientation on the outsole. However, the use of elongate or asymmetric studs causes the problem that their orientation in the fitted state, as explained above, is of decisive importance for the performance when running. For this reason, the conventional connection between outsole and stud by means of a screw mechanism was no longer suitable, since attaching and tightening the stud does not allow a defined final position of the stud to be achieved. For this reason, it has been necessary to find alternative fastening mechanisms for elongate or asymmetric studs allowing the stud to be fitted in the desired orientation or position with respect to the sole of the shoe. In order to avoid a risk of injury and to provide the desired grip properties, it was furthermore necessary for suitable fastening mechanisms to ensure that the stud was fitted so that it was secured against rotation. A possible fastening mechanism for elongate or asymmetric studs of this nature is described, for example, in US-A-5,628,129. According to this known approach, an outsole is provided which has a multiplicity of receiving openings for the exchangeable studs, which for their part comprise a base part and a grip part. The base part comprises a multiplicity of engagement projections which extend from the base part on the circumferential side. In order to connect the stud elements to the outsole, the former are introduced into the receiving openings in such a manner that the engagement projections are in alignment with engagement notches which are provided in the receiving openings in the outsole. The stud element is then fixed in the outsole by rotating the respective stud element through a defined angle. A further possible solution to the problems discussed above is also known from EP 0,815,759. The elongate, exchangeable football studs described in this document have a polygonal base which can be introduced into a recess of complementary design in the region of the outsole. In this way, it is ensured that the elongate stud can be fastened in a rotationally secure manner in the desired orientation. As in the conventional approach, the connection between stud and outsole is achieved by means of a screw which extends through a continuous opening in the stud into a screw thread of corresponding design in the outsole. In this case, the screw head is situated inside a recess in the outer end of the stud. Another possibility is disclosed in the the German Utility Model DE 298 07 082. This document describes an elongate stud having an internal slit into which from the bottom side a wedge-like element is inserted in order to outwardly bend the upper end of the stud. The upper end comprises sideways extending projections engaging corresponding recesses in the receptacle for the stud in the sole. To release the stud an opening is provided on the side of the stud so that by means of a special tool the wedge-like element can be again outwardly pushed. A further approach is described in the German Utility model DE 81 35 233. In this case the stud is mounted to the sole by means of two latching bars which are manually pushed in opposite directions to engage corresponding recesses in the receptacle of the sole. Subsequently the latching bars are fixed in their relative position by a screw operated from below. The solutions which are known from the prior art, however, have a large number of drawbacks. In the prior art mentioned above in accordance with US-A-5,628,129, a substantial rotary action exerted on the stud element may lead the latter to become unscrewed from the receiving opening, resulting in a considerable risk of injury. In the prior art according to EP 0,815,759, problems arise as a result of the fact that the screw head is arranged inside a recess in the outer end of the stud. Owing to the large number of sharp edges, this results, particularly if the screw becomes loose unintentionally, in a considerable risk of injury, particularly if players come into contact with the studs. For this reason alone, such a solution would not be licensed by FIFA. Furthermore, practical problems arise: it is clear that when the boot is used, for example, on grass the stud becomes very dirty, with the result that it can only be exchanged with a considerable level of effort. Furthermore, when running on hard surfaces, the wear to the outer end of the stud also quickly leads to the screw head becoming abraded, making it impossible or at least difficult subsequently to exchange the stud. Furthermore, the outer surface of the stud is usually relatively small, in order to allow it to penetrate optimally into the ground. This geometry also means that it is only possible to use a comparatively small screw, since the screw head should never project beyond the end face of the stud. However, if it is only possible to use small screws, this leads to the fastening of the stud being insufficient. The problem underlying the present invention is therefore that of providing exchangeable, preferably elongate studs for boots which meet FIFA requirements with regard to the risk of injury and the reliability of the connection and which can be produced inexpensively and exchanged without problems. 3. Summary of the invention The above problems are resolved, according to the invention, by means of a shoe according to claim 1. In detail, a stud-fastening mechanism engages behind a locking recess which is provided in or on the outsole and thus becomes wedged or latched in the locking recess. In the preferred embodiment according to claim 2, the stud is fastened on the one hand by means of a fastening part which is provided integrally on the stud and on the other hand by means of the stud-fastening mechanism according to the invention, the fastening part, which is to be introduced into the locking recess, ensuring that the stud is fixed against rotation after it has been fitted. The releasable connection between stud and sole is produced, according to the invention, by the locking mechanism being displaced, relative to the stud, into the position in which it engages behind the locking recess. In the preferred embodiment according to claim 3, the fastening mechanism according to the invention is arranged in a cavity provided in the interior of the stud and can be actuated through the stud (side)wall. This has the advantage that the likelihood of the screw becoming dirty and causing injury is minimized. The fastening mechanism comprises a locking hook which is arranged in an essentially displaceable manner and can be actuated by means of a simple screw element. A fastening mechanism of this nature is, on the one hand, particularly reliable and, on the other hand, particularly inexpensive to produce. The preferred embodiment according to claim 5 allows the fastening mechanism to be fastened in a particularly inexpensive and, at the same time, reliable manner by means of a securing pin in the interior of the stud. The shoulder which is provided on the screw element according to claim 6 and serves as a stop ensures that the screw cannot move out of the stud. In this way, a risk of injury is substantially precluded. The preferred embodiment according to claims 7 and 8 allows particularly simple fitting of the stud in the locking recess in the sole. The stud is simply pushed into the locking recess, where it engages in a rotationally secure manner. By actuating the screw element, the stud is definitively locked in the locking recess. The preferred embodiment according to claims 9 and 10 has the advantage that the stud is basically drawn into the locking recess when being fastened. This leads to a particularly firm and secure positioning of the stud. Providing the locking recess according to the invention by means of a holding frame in accordance with claim 11 has the advantage of efficient production from a manufacturing technology viewpoint, combined with the possibility of selecting the most suitable materials both for the holding frame and for the outsole. The preferred embodiment according to claims 12 and 13 has the advantage of allowing an optimum shape of the stud, according to current knowledge, with regard to the grip of the shoe. 4. Brief description of the drawing Further advantageous embodiments of the present invention will emerge from the following description of the drawing, in which: Figure 1a shows a view from below of an outsole of a shoe having the studs according to the invention; Figure 1b shows a lateral section on line A-A from Figure 1a, with a fitted stud (on the left) and an unfitted stud (on the right); Figure 2a shows a section through a stud according to the invention on line A-A from Figure 1a, without the stud-fastening mechanism according to the invention, with the securing pin removed; Figure 2b shows a rear view of the stud according to the invention; Figure 2c shows a view from below of the stud according to the invention in accordance with Figure 2a; Figure 2d shows a detailed view of the stud-fastening mechanism according to the invention; Figure 3a shows a view from below of the holding frame according to the invention; Figure 3b shows a side view of the holding frame according to the invention on line A-A from Figure 3a; and Figure 3c shows a lateral section on line B-B from Figure 3a. 5. Description of the preferred embodiments The currently preferred embodiments of the present invention are described below. However, it is expressly pointed out that the present invention is not limited to these embodiments, but rather that modifications are possible within the scope of the appended claims. In particular, the present invention - as mentioned - is not intended to be limited to football studs, but rather to be used for all types of shoes in which standard profiled soles are insufficient to ensure that the wearer does not slip, but rather projections which penetrate into the ground (studs, spikes, etc.) are used, which projections are releasably connected to the shoe sole. The present invention relates to exchangeable studs 20 as illustrated in Figure 1. Figure 1a shows part of a sole 10 of a shoe (not shown), as viewed from below. As can be seen, the studs 20 are preferably of elongate design, are of a rounded wedge shape in cross section and taper towards their side which interacts with the ground. As can be seen from Figure 1a, the studs according to the invention taper asymmetrically towards their outer side. This allows the grip resistance to be adapted in a targeted manner depending on the type of sport. In the embodiment shown in Figure 1a, for example, the studs have a grip which is increased towards the steeper side (the right-hand side of the studs). Figure 1b shows a section through the studs 20 according to the invention on line A-A from Figure 1a. In addition to the studs 20 having the stud-fastening mechanism 100 which is described in more detail below, it is also possible to see the holding frame 55 according to the invention which defines the locking recess 50 in the stud. The two parts of Figure 1b respectively show a fitted stud 20 (on the left) and a stud 20 shortly before it is fitted (on the right). The detailed structure of the stud 20 according to the invention and of the holding frame 55 according to the invention will be described below with reference to Figures 2 and 3. Figure 2a shows the stud 20 according to the invention in longitudinal section on line A-A from Figure 1a, but without the stud-fastening mechanism 100 according to the invention and without the securing pin 130 which is to be described in more detail below. As can be seen from Figure 2a, the stud 20 essentially comprises two parts, namely a part 25 which interacts with the ground or surface and a fastening part 30 which is used to fasten the stud 20 in the locking recess 50 which is to be described below. In other words, when the studs are fitted it is only possible to see the interaction part 25, while the fastening part 30 is sunk into the locking recess 50 (cf. also Figure 1b). As can also be seen from Figure 1a, the fastening part 30 preferably also has a locking shoulder 32 which extends at least partially around its lower edge and interacts with an undercut 52', which is of complementary design and is to be described below, in the locking frame 55, in order to fasten the stud in the locking recess 50. Furthermore, the stud 20 preferably has a cavity 40 into which the stud-fastening mechanism 100 according to the invention is introduced during subsequent fitting. Furthermore, the stud 20 has a through-bore 132, which extends essentially parallel to the underside of the stud, in the region of the fastening part 30. Furthermore, there is a further through-bore 26 towards a narrow side wall of the fastening part 30. Preferably, the stud 20 according to the invention is made from magnesium, aluminium or plastic. As an alternative, it is also possible to coat magnesium or aluminium with plastic. It will be clear to the person skilled in the art that all possible stud materials of sufficient hardness are suitable. Figures 2b and 2c show a side view and a view from below of the stud according to the invention, these views providing a more detailed illustration of its outer shape and of the shape of the cavity 40. Figure 2d provides a detailed illustration of the stud-fastening mechanism 100 according to the invention. It essentially comprises two interacting parts, namely a locking hook 110 and a screw element 120. Both elements are preferably made of metal, such as for example aluminium. However, various other suitably strong materials, in particular metals, are also suitable. The locking hook 110 comprises a hook end 112 and a support end 113. A through-bore 115, which is provided with an internal screw thread (not shown), is provided inside the support end 113. The screw element 120 according to the invention, the screw threads of which are diagrammatically depicted in Figure 2d, extends through this internal screw thread. The screw element 120 preferably has a projecting shoulder 122 in the immediate vicinity of the screw head, which shoulder, after the stud-fastening mechanism 100 has been fitted, comes to bear against the inner wall of the cavity 40 in the region of the through-opening 26, where it serves as a stop (cf. also in this respect Figure 1b). Furthermore, the screw element 120 comprises a bearing part 123 which, with the stud-fastening mechanism 100 fitted, comes to bear against a surface 43 of complementary design inside the opening 40 in the stud 20. In the fitted state, the screw element 120 is thus mounted at two positions inside the cavity 40 with respect to the stud 20, namely, on the one hand, in the region of the bearing surface 43 and, on the other hand, in the region of the bearing surface 42. Furthermore, the cavity 40 in the stud 20 is shaped in such a way as to define a free space 45, through which the upper end of the support 113 can move parallel to the dot-dashed bearing axis of the fastening mechanism 100 when the screw element 120 is screwed through the opening 26 from the outside. In order to fit the stud according to the invention, the stud-fastening mechanism 100 is preassembled as illustrated in Figure 2d and is then introduced into the cavity 40 in the stud 20 from below until it has reached the position shown in Figure 1b. Then, the securing pin 130 is driven into the stud through the opening 132 until it has reached the position shown in Figure 1b. The preference for providing a projection 131 on the securing pin 130 prevents the securing pin 130 from moving out of the opening 132 again. In this way, the fastening mechanism 100 is prevented in a simple manner from falling out of the stud 20 in the unfitted state. Secondly, this also provides the mating surface for the bearing surface 43. Finally, Figure 3 provides a detailed illustration of the holding frame 55 according to the invention in the unfitted state, which frame is incorporated in the outsole 10 when the latter is produced. If the holding frame 55 is made of plastic, the join to the outsole is preferably produced by a chemical process. For this purpose, the holding frame 55 may be inserted into the injection mould which is used to produce the outsole 10. Nylon 11 or Nylon 12 is currently the preferred material for the outsole. Nylon 11 is currently the preferred material for the holding frame 55. However, any other hard plastic is also suitable. As an alternative, the holding frame 55 may also be made of aluminium or steel. In the case of a holding frame 55 made from metal or steel, this frame is either clipped into a suitable recess in the sole which has already been produced, or else the holding frame 50 - like a plastic holding frame - is inserted into the mould and the plastic is then injected around it. The latter variant is currently preferred for metal holding frames. In this case, however, the join to the plastic sole is mechanical, i.e. suitable holes or apertures into which the liquid plastic for the sole penetrates and hardens has to be provided in the holding frame 55. The longitudinal and transverse sections through the holding frame 55 which are illustrated in Figures 3b and 3c clearly show the locking recess 50 according to the invention with the undercuts 52 and 52' which ensure that the stud 20 according to the invention is held securely in the locking recess 50. In order to fit the stud 20, the latter is initially introduced into the locking recess 50 in such a manner that the locking shoulder 32, which advantageously extends at least part way around the circumference of the fastening part 30 (cf. Figure 2a), comes to lie below the undercut 52', which is advantageously of complementary design, and engages behind the latter. Particularly advantageously, either the undercut 52' and/or the locking shoulder 32 are designed so as to taper conically, as described in more detail below. When this fitting state has been reached, the remaining part of the stud (in the illustration in accordance with Figure 2a the right-hand part of the stud 20) is pushed further into the locking recess 50 until the fastening part 30 has been sunk completely into the locking recess 50. Advantageously, the locking recess 50 is dimensioned in such a way that even in this state the stud is prevented from falling out as a result, for example, of the sole 10 being turned. Then, the screw head of the screw element 120 is screwed through the through-opening 26 by means of a suitable tool (in this case a screwdriver). Owing to the fixed mounting of the screw element 120, this leads to the locking hook 110 being displaced parallel to the axis shown in dot-dashed lines in Figures 2a and 2d. This leads to the hook end 112 of the locking hook 110 engaging behind the locking recess 50 in the region of the undercut 52. If the undercut 52 and/or the hook end 112 are designed so as to taper conically (cf. also the dashed line in Figure 2d), tightening the screw element 120 leads to the fastening part 30 of the stud 20 being "pulled" into the locking recess 50. Since the longitudinal dimensions of the stud 20 are increased by the lateral movement of the hook-shaped end 112, the locking recess 50 illustrated in Figure 3a is elongated, leading to a further securing of the position of the fastening part 30 in the locking recess 50. It immediately becomes clear that the stud 20 according to the invention which has been fitted in in this way on the one hand is very inexpensive to produce and on the other hand can be fastened to the sole 10 in a manner which is secured against rotation, avoiding any risk of accidents. In the above-described embodiment of the present invention, the stud-fastening mechanism 100 according to the invention comprises only a single displaceable locking hook and a fastening part 30 which is formed integrally with the stud 20. However, it will be clear to the person skilled in the art that as an alternative to the fastening part 30 it is also possible to use a further locking hook or a multiplicity of locking hooks which are in each case actuated by means of screw mechanisms, for example, so as to engage into or behind a locking recess or locking recesses provided on the sole. Furthermore, it will be clear to the person skilled in the art that the locking recess does not necessarily have to be provided in the interior of the sole 10, but rather - as is known from the prior art - may also be provided in the interior of a separately provided base. Finally, it is pointed out that it is possible to vary both the shape of the locking hook 110 and the actuation mechanism of the locking hook within the scope of the appended claims.

Claims: Shoe, in particular sports shoe or walking boot, which has an outer sole (10) and at least one stud (20) which is releasably connected thereto and interacts with the ground when the shoe is used, in which shoe a. said at least one stud (20) comprises a stud-fastening mechanism (100); and b. the outer sole (10) has at least one locking recess (50); c. the stud fastening mechanism (100) is moved into a position in which it engages behind the locking recess (50) in order to produce the releasable connection, characterized in that d. the stud fastening mechanism (100) comprises a screw element (120) and a locking hook (110), wherein the screw element (120) interacts with the locking hook (110) to displace the looking hook parallel to the longitudinal axis of the screw element (120) in said engagement position. Shoe according to claim 1, wherein the at least one stud (20) comprises an interaction part (25), which interacts with the ground when the shoe is being used, and a fastening part (30), in which shoe the fastening part (30) is introduced into the locking recess (50), which is of complementary design, in order to fit the stud (20). Shoe according to claim 2, wherein the stud (20) has a cavity (40) which extends from the interaction part (25) and opens out towards the fastening part (30), in which cavity the fastening mechanism (100) is arranged, it being possible to move the fastening mechanism (100) through the wall of the interaction part (25), from a fitting position into said position, in which it engages behind the locking recess (50), and vice versa. Shoe according to claim 3, wherein the locking hook (110) has a through-opening (115) which is provided with an internal screw thread and interacts with the screw element (120), which is of complementary design and can be actuated through the wall of the interaction part (25). Shoe according to claim 4, wherein the combination of locking hook (110) and screw element (120) is held in the cavity (40) by means of a securing pin (130). Shoe according to claim 4 or 5, wherein the screw element (120) has a projecting shoulder (122) which serves as a stop. Shoe according to any of the claims 3 to 6, wherein the fastening part (30) comprises a locking shoulder (32), which extends at least partially on the circumferential side and engages behind an undercut (52'), which is preferably of complementary design, in the locking recess (50). Shoe according to claim 7, wherein the displaceable locking hook (110) has a hook-shaped end (112) and is mounted in the cavity (40) in such a manner that the hook-shaped end (112) is essentially aligned with the locking shoulder (32) of the fastening part (30). Shoe according to claim 8, wherein the locking shoulder (32) of the fastening part (30) and / or the hook-shaped end (112) of the looking hook (110) taper towards the interaction part (25). Shoe according to any of the claims 7 to 9, wherein the undercut (52, 52') in the locking recess (50) tapers towards its open end. Shoe according to any of the claims 1 to 10, wherein the undercut (52, 52') and the locking recess (50) are formed by a holding frame (55), which is incorporated into the outer sole (10) and consists of a hard plastic or of a metal. Shoe according to any of the preceding claims, wherein the at least one stud (20) is in the shape of a rounded wedge in cross-section and tapers towards the end of the interaction part (25). Shoe according to claim 12, wherein the taper towards the end of the interaction part (25) is asymmetric.

Inventors: HELLER MANFRED, HELLER, MANFRED
Applicants: ADIDAS INT MARKETING BV, ADIDAS INTERNATIONAL MARKETING B.V.
Application year: 1999
Main classification: A43C15
IPC codes: A43C15, A43B5, A43B13