Interface plate for ski safety binding
FIELD OF THE INVENTION 
     The invention relates to an interface plate for an alpine ski safety binding. 
     BACKGROUND OF THE INVENTION 
     Numerous types of alpine ski safety bindings are known, and, in particular, front binding elements, which comprise a base by means of which the binding is assembled to the ski. Many of these bindings are made of a plastic material or, at the least, have a base made of a plastic material. 
     It thus happens that, when the binding is assembled to the ski, a space is created between the upper surface of the ski and the binding base. Snow or dirt can penetrate into this space and impair the operation of the binding. 
     Some interface plates exist whose main function is to hold the assembly screws in place in their orifices in the base until they are tightened in the ski. These plates perform, however, no impermeability function between the base and the upper surface of the ski. 
     SUMMARY OF THE INVENTION 
     One of the objects of the present invention is to propose an interface plate which provides effective impermeability between the base of the binding and the ski. 
     Another purpose of the present invention is to object an interface plate which can be easily assembled to the binding at the factory. 
     A further purpose of the invention is to object an interface plate which holds the assembly screws belonging to the binding in their orifices in the base until the binding is assembled to the ski. 
     Other objects and advantages of the invention will emerge during the following description. 
     The interface plate according to the invention has an edge extending along at least one portion of the lateral edges of the binding base, and incorporates, on either side of its median zone, a lateral element inclined substantially downward and outward, in such a way that, when the base is assembled to the ski and the plate is squeezed between the base and the ski binding, the lateral elements straighten into a horizontal position, thereby forcing the edges to flatten along the lateral edges of the base. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood with reference to the following description and to the attached drawings. 
     FIG. 1 is a perspective view of an interface plate according to a first embodiment of the invention. 
     FIG. 2 is a side view of a front binding equipped with the plate in FIG. 1. 
     FIGS. 3, 4, and 5 illustrate a mode of use of the plate during manufacture and assembly of the binding on the ski. 
     FIG. 6 is a perspective view of a variant of the interface plate according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows an interface plate 1 designed to equip a front binding 7. The plate 1 has a bottom 2 whose surface and outer contour substantially correspond to those of the base and of the plate supporting the binding 7. In the embodiment shown, the bottom further incorporates various recesses, whose existence and nature are not restrictive. 
     The plate is preferably made of an elastically-deformable plastic material, e.g., a polypropylene or fiber-loaded polyamide. However, any elastically-deformable material would also be suitable. 
     The plate 1 has, over a portion of its periphery, an edge 3 which is designed to rise along the lateral faces 9 of the base 6 of the binding 7. 
     The bottom of the plate has a median zone, here formed by a median part 4 extending longitudinally and by two lateral elements 5 extending on either side of the median part 4. The edges 3 are attached to the lateral elements 5. 
     The boundaries separating the median part 4 and the two lateral elements 5 have been schematically represented by dotted lines 18 in FIG. 1. These boundaries are, in this case, parallel and run longitudinally. 
     According to the invention, the lateral elements 5 of the plate are inclined downward and outward. The inner face of the edges 3 then opens slightly outward. 
     The angle of inclination between the upper surface of the lateral element 5 and the horizontal is preferably greater than the angle of inclination between the inner surface of the edge 3 and the vertical. Accordingly, when the binding is assembled to the ski, the bottom 2 of the plate is squeezed between the base 6 of the binding and the upper surface of the ski. This squeezing action forces the lateral elements 5 to straighten into a horizontal position in alignment with the median part 4, and the edges 3 are then stressed so as to be pressed against the lateral faces 9 of the base 6. Given the difference between the angles mentioned above, the edges 3 exert an elastic support force on the lateral faces 9 of the base 6, thereby providing effective impermeability in this area. In fact, the edges 3 block up the space potentially created between the base and the upper surface of the ski. 
     Good results have been obtained using an angle of approximately 10° between the lateral elements 5 and the horizontal, and an angle of approximately 3° between the edges 3 and the vertical, i.e., an angular difference of 7°, which determines the force with which the edges 3 are pressed against the lateral faces of the base 6. This arrangement is, of course, not restrictive, and other angular values are suitable. 
     According to a preferred embodiment, the plate 1 has, in the area of the screws used to mount the base on the ski, disks 10 which extend the median part 4 laterally. These disks have an orifice 11 whose diameter is substantially less than the diameter of the threaded portion of a screw. Accordingly, these disks and their orifices can firmly hold in place a binding-assembly screw, whose threaded portion engages in the orifice. 
     Thus, it is possible, during manufacture, to hold the plate beneath the base using screws, and, moreover, to retain the assembly screws in their orifices by means of the plate. 
     FIGS. 3 and 4 illustrate this function of the plate. As has been stated above, the lower faces of the edges 3 open substantially outward. In this way, the base 6 of the binding can be positioned above the plate and be easily positioned inside the edges. The screws 12 are then inserted in their orifices, and their threaded portions engaged in the orifices 11 in the plate. Accordingly, and as illustrated in FIG. 4, the screws 12, the plate 1, and the base 6 form a one-piece assembly. This operation may advantageously be performed automatically. 
     The binding is prepared in this way until it is mounted on the ski. FIG. 5 illustrates this assembly, and, as stated previously, tightening the screws 12 squeezes the plate 1 between the base 6 and the ski, thereby straightening the lateral elements 5 into a horizontal position and flattening the edges 3 against the lateral faces of the base. 
     FIG. 6 represents a variant, in which the boundaries between the central part 14 and the lateral elements 15 (represented schematically by dot-and-dash lines 17), are oblique and converge toward the front of the binding. Thus, the boundaries 15 intersect with the edges 13 at the rear of the binding, thereby making it possible to produce this edge in continuous fashion from the front to the rear of the binding, even though only one portion is connected to the lateral elements 15 of the plate. 
     The present description is not restrictive, and other variants are possible. In particular, depending on the areas in which one wishes to flatten the edge against the base, the lateral elements of the plate could be produced differently, e.g., segmentally.