Antifriction device, particularly for ski bindings

Abstract: An antifriction device, particularly for ski bindings including a first body (4) which is fixed to the ski (2) or is associable therewith and with which a second body (5) is slidingly associated with the possibility of sliding along an axis which is longitudinal to the ski. A tab (9) is removably or permanently associable with the second body, and a plate (12) is freely pivoted to the tab perpendicular to said ski and at the region underlying the heel and/or tip of a ski boot. Thus, upon the activation of the safety release of the binding, the tab performs a translatory and rotary motion which facilitates the disengagement of the boot from the binding.

Description: The present invention relates to an antifriction device particularly usable in ski bindings. Antifriction devices used in ski bindings, particularly at the tip elements, are currently known. Some of said devices are simply constituted by a plate which is directly coupled to the ski and is made of antifriction material, for example of the type commercially known by the trade-mark TEFLON: the sole of the boot rests on said plate once the binding has been closed. Said known devices, however, have the disadvantage of not dynamically facilitating in any way the disengagement of the boot from the binding; the presence of mud on the surface of the boot heel can furthermore defeat the characteristic due to the material which constitutes said plate. As a partial solution to this disadvantage, plates are known which are allowed to perform a mechanical sliding, along an axis which is essentially transverse to the ski, by virtue of adapted ball bearings which interact with said plates and reduce, during release, the friction between the sole of the boot and the ski; the movement for the release of said boot from said binding is thus facilitated. Even this solution, however, is not optimum, since during release there is no reduction in the friction between the sole of the boot and said plate. As a partial solution to these disadvantages, devices are known, such as shown in FR-A-2 473 328, wherein the plates are connected to the tip element so that a rotation of said tip element leads to a rotation of the plate as well, so as to facilitate the release of the boot from the binding. The disadvantage of said solutions consists of the fact that the movement of the plate is activated directly by the movement of the tip element; thus, each movement of the tip element is univocally matched by a movement of the plate, regardless of the value of the friction occurring between the sole of the boot and the surface of said plate. This is a considerable limitation, since even a slight movement of the tip element, due for example to the stresses imparted thereto by the ski while skiing, can induce a release of the boot which is neither necessary nor desired. A slight rotation of the tip element in fact imposes a rotation to the plate and thus arranges the boot off-axis with respect to the ski, and consequently with respect to the binding, facilitating its release. The aim of the present invention is therefore to eliminate the disadvantages described above in known types by providing a device which allows to reduce the friction between the sole of the boot and the surface of the ski during safety release from the binding. Within the scope of the above aim, another important object is to provide a device which allows to activate the safety release of the binding in case of actual need, without said safety release occurring upon small rotations or movements of said binding. Another object is to provide a device which is reliable and safe in use. Not least object is to provide a device which associates with the preceding characteristics that of being structurally simple and of having modest costs, said device being obtainable with conventional known machinery. This aim, these objects and others which will become apparent hereinafter are achieved by an antifriction device in combination with a ski binding as defined in the appended claim 1. Further characteristics and advantages of the invention will become apparent from the detailed description of a particular embodiment, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a top view of the device applied to a heel element of a ski binding; figure 2 is a sectional view of the antifriction device, taken along a median plane which is longitudinal with respect to the binding. With reference to the above figures, the reference numeral 1 indicates a heel element of a binding for a ski 2 with which the antifriction device, indicated by the numeral 3, is associated. The heel element 1 is constituted by a first body 4 which is fixed to the ski 2 or is associable therewith and with which a second body 5 is internally slidingly associated with the possibility of sliding along an axis which is longitudinal to said ski 2. The mutual movement of the first and second bodies, the near-maximum extent whereof is indicated in figure 2 by the letter A, is allowed by adapted elastic means, including in particular the springs 6, 7 and 8 which are part respectively of means suitable for allowing the automatic reset of the binding in case of safety release and of means for compensating the deflection of the ski during skiing, to achieve an elastic recovery which allows to avoid an unnecessary release of the boot. The antifriction device 3 comprises at least one tab 9 which, in the particular embodiment illustrated, is rigidly associated with the second body 5 and protrudes therefrom toward the tip of the ski 2 along a median longitudinal axis. Tab 9 is arranged adjacent to the ski 2, in order to lie below the jaw 10 of the heel element and below the sole of the boot. The length of said at least one tab 9 is therefore such as to protrude beyond the jaw 10, and at least one plate 12, which preferably has a circular plan shape, is freely pivoted, along an axis which is perpendicular to the ski 2, to the terminal end 11 of said tab. In the use of the ski binding, following a safety release in which the pressure exerted by the heel of the boot on the jaw 10 of the heel element ceases, the second body 5 moves toward the tip of the ski due to the spring 8, allowing the opening of said jaw 10 and thus the automatic reset of the heel element by virtue of the adapted means provided therein. The presence of the tab 9 and of the plate 12 allows to reduce the friction between the heel of the boot and the surface of the ski during said safety release; the tab 9 can in fact perform a translatory motion, along an axis which is longitudinal to the ski 2, which is activated by the movement of the second body 5, whereas the plate 12 can perform a rotary motion with respect to the tab 9 with respect to an axis which is vertical to said ski 2. Said rotation occurs by virtue of the friction which exists between the plate 12 and the sole of the boot when said boot is subjected to a lateral release in extreme conditions. It has thus been observed that the invention has achieved the intended aim and objects, a device having been provided which allows to reduce the friction between the sole of the boot and the surface of the ski during a safety release from the binding. An advantage offered by this invention consists of the fact that during the release of the boot the sole thereof rotates substantially with respect to the tibial axis of the leg and, in some cases, moves longitudinally with respect to the ski: therefore, with respect to the prior art, in which a possible plate can be freely pivoted directly at the ski, the heel has a greater rotation radius with respect to that of said plate, said radius deriving from the simple rotary motion or from the compound rotary and translatory motion. In the illustrated solution, the simultaneous translatory motion of the tab 9 thus allows to compensate the difference between the radius of the rotation of the heel of the boot and that of the plate 12, thus allowing to follow the various movements of the sole without inducing relative motions between the sole and the plate 12 which lead to passive forces, i.e. to friction. The device furthermore allows to activate the safety release of the binding in case of actual need, without said safety release being imposed upon small rotations of the tip element of the ski binding. The device furthermore has modest manufacturing costs and is structurally simple. The tab 9 may naturally be rigidly associated or coupled or applied on the second body 5, all this being done using known connection means. The dimensions and the materials which constitute the individual components of the device may naturally also be the most appropriate 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 scope of each element identified by way of example by such reference signs.

Claims: Antifriction device in combination with a ski binding comprising a first body (4) which is associable with a ski (2), a second body (5) being slidingly associated with said first body and being adapted to slide along an axis which is longitudinal to said ski when the binding is associated therewith, wherein at least one tab (9) is associated with said second body, at least one plate (12) being freely pivoted to said tab perpendicular to said tab and at a region arranged for supporting a ski boot to be associated with said binding. The combination according to claim 1, comprising a heel element (1) constituted by a first body (4) associated with a ski (2), a second body (5) being internally slidingly associated with said first body, with the possibility of sliding along an axis which is longitudinal to said ski, elastic means (6,7,8) being arranged within said first and second bodies, said elastic means being respectively a part of means suitable for allowing the automatic reset of the binding upon safety release and for compensating the deflection of the ski while skiing to allow an elastic recovery which allows to avoid an unnecessary release of said ski boot, wherein said heel element comprises said at least one tab (9) which is rigidly associated with said second body (5) and protrudes therefrom toward the tip of said ski. The combination according to claim 2, characterized in that said at least one tab (9) is arranged adjacent to the upper surface of said ski so as to lie below a jaw (10) of said heel element (1) and below the sole of the boot. The combination according to claim 3, characterized in that said at least one tab (9) has such a length as to protrude beyond said jaw (10), said at least one plate (12) being freely pivoted at said tab terminal end along an axis which is perpendicular to said ski. The combination according to claim 4, characterized in that said at least one plate (12) has a circular plan shape. The combination according to one or more of the preceding claims, characterized in that said at least one tab (9) can be rigidly associated with said second body. The combination according to one or more of the preceding claims, characterized in that said at least one tab (9) protrudes from said second body (5) toward the tip of said ski along a median axis which is longitudinal to said ski. The combination according to one or more of the preceding claims, characterized in that said at least one tab (9) is rigidly associated with said second body (5), provided at the tip element of said ski binding, said at least one tab protruding toward the rear end of said ski.

Inventors: BAGGIO GIORGIO, BATTISTELLA MIRCO, GORZA ROBERTO, BAGGIO, GIORGIO, BATTISTELLA, MIRCO, GORZA, ROBERTO
Applicants: NORDICA SPA, NORDICA S.P.A
Application year: 1991
Main classification: A63C9
IPC codes: A63C9