Patent Publication Number: US-6336279-B1

Title: Ski boot

Description:
BACKGROUND OF THE INVENTION 
     The subject of the present invention is a ski boot consisting essentially of a shell forming the sole and the upper and of a lower-leg collar articulated on the shell and equipped with an inner reinforcement element fixed to the collar and reinforcing the side of the boot which corresponds to the inner side of the leg. 
     A boot of this type is known from Patent FR 2,649,594, the content of which is incorporated by reference. In this boot, the collar is equipped with a reinforcement having a relatively rigid plate fixed adjustably and removably to the inner face of the collar. This plate is made from synthetic material, but could be made from metal or from glass fibers or from carbon fibers. Its aim is to improve the quality of transmission of the sideways force of the leg to the ski so as to improve ski control. Otherwise, this boot behaves as a boot without reinforcement, particularly as regards being put on and taken off. 
     U.S. Pat. No. 5,867,924, the content of which is incorporated by reference, discloses, moreover, a ski boot whose collar is equipped with a front plate serving as a support for the tibia. In U.S. Pat. No. 5,819,442, the content of which is incorporated by reference, furthermore, describes use of auxiliary reinforcement pieces of asymmetric shape which, depending on their position, make it possible to improve the dynamic characteristics of the boot either for slalom and skiing on ice or for downhill skiing. These pieces are fixed removably under the front part of the collar. 
     SUMMARY OF THE INVENTION 
     The present invention has a different aim. Its object is to improve comfort and to make it easier to put the boot on and to take it off without prejudicing the performance levels of the boot, i.e. its dynamic characteristics. In other words, the invention is a boot manufactured using flexible and therefore comfortable materials, the dynamic characteristics of which, particularly support toward the inside and toward the front, and flexing, are modified by the addition of the reinforcement. 
     To this end, the boot according to the invention is defined in that the reinforcement element has a semi-rigid piece in the form of a half-collar fixed to the collar, the semi-rigid piece surrounding the upper edge of the shell over slightly more than half of the periphery of the collar, and having a means for making the reinforcement interfere with the shell so that the reinforcement element controls the flexibility of the boot during flexing of the leg. 
     In this way, it is possible to produce a boot whose shell is relatively flexible and comfortable, in which inner-side support and tibia support is ensured by the reinforcement piece, when the collar is closed. When the collar is opened to be put on or take off the boot, it releases the flexibility of the shell in such a manner that the latter may be more easily put on and taken off. 
     A further considerable advantage of the invention is the possibility, due to a minimum shell flexibility (for example 54 Shore D) and a relatively flexible collar, of producing boots of different rigidity by means of the addition of a reinforcement which is varies in thickness. This greatly facilitates stock management. 
     According to a preferred embodiment of the invention, the inner side of the upper edge of the shell has a V-shaped notch and the reinforcement element has, on its inner face, a wedge-shaped projection which, in the closed position of the boot, fits into the V-shaped notch. The effect of the V-shaped notch is to facilitate opening of the shell for putting the boot on, the wedge-shaped projection of the reinforcement element eliminating this additional flexibility once the boot has been put on. 
     Moreover, the reinforcement piece advantageously bears frontally against the upper edge of the shell, ensuring continuity of thickness and continuity of the inner face of the shell. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The appended drawings show, by way of example, an embodiment of the invention and a variant thereof. 
     FIG. 1 is an exploded view of the shell, collar and reinforcement element. 
     FIG. 2 is a side, cross-sectional view, on a larger scale, through one joint of the collar on the shell. 
     FIG. 3 is a side, partial break-away view of an alternate embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The boot shown has (1) a shell  1  which forms, in a known manner, the upper  2  which closes over the front of the boot via two tabs and the sole  3  of the boot, (2) a collar  4  articulated on the shell  1 , on each side of the latter, at two opposite points, such as the point  5 , by means of a rivet  6  (FIG.  2 ), and (3) a reinforcement element  7 . All these pieces are injection-molded pieces made, for example, from polyurethane with the addition of an additive so as to obtain a greater or lesser rigidity, this being in a known manner. 
     The material of the shell  1  has, for example, a rigidity of 54 Shore D, which is approximately the minimum hardness for such an application. The collar  4  is relatively flexible whereas the reinforcement element  7  has a rigidity which is greater than that of the shell  1 . 
     The reinforcement element  7  extends over slightly more than half of the periphery of the collar  4 . At the front, it has a stud  8  which, from the inside of the collar  4 , fits into a hole  9  in said collar and, at the rear, a second stud  10  which fits into a hole  11  made in the back of the collar  4 . The reinforcement element  7  therefore extends on each side of the hole  11  so that it partially surrounds the bottom of the calf. 
     On its inner face, the reinforcement element  7  has a wedge-shaped projection  12  oriented substantially vertically. This projection  12  is formed from an excess thickness of the material of the reinforcement element. For its part, the upper edge of the shell  1 , on the side corresponding to the inside of the foot, has a notch  13  which is also V-shaped and is geometrically similar to the shape of the projection  12  and substantially of the same extent. When the pieces shown are assembled, the projection  12  is engaged in the notch  13 . 
     The effect of the notch  13  is to increase the deformation capacity of the upper part of the shell  1  and consequently to facilitate putting the boot on and taking it off, releasing the shell tabs. On the other hand, when the collar  4  is tightened around the leg, the notch  13  is occupied by the projection  12  in such a manner that the shell becomes nondeformable and that flexibility is greatly reduced. Thus, by means of a single reinforcement, inner front support (and thus ski behavior) and dynamic rigidity of the boot are simultaneously improved. 
     FIG. 2 shows that the reinforcement element  7  has a thinned lower part  7   a  surrounding the upper edge of the shell  1 . Above this thinned part, the reinforcement element  7  has a relatively thick zone  7   b  bearing frontally against the upper edge  14  of the shell  1  so as to ensure continuity of the inner face  15  of the shell. Moreover, above the lower edge of the part  7   a , the shell thins slightly, as does the collar  4 . A certain continuity of the overall thickness is thus ensured in the superposition zone of the shell, of the collar and of the reinforcement element. 
     Naturally, the boot has conventional tightening means, such as buckles, and also an inner comfort boot. 
     According to an alternate embodiment, the angle of the notch  13  is larger than the angle formed by the projection  12 , and the space remaining between at least one side of the notch  13  and the projection is filled with an elastomeric material. The angle of the notch  13  is enlarged only towards the front, so that the elastomer would be only in front of the projection, thus conferring a degree of elasticity during flexing of the leg. 
     FIG. 3 shows a variant embodiment in which the projection  12  is replaced by a stud  16  and the V-shaped notch  13  is replaced by an aperture  17  cut into the shell  2 , in the shape of an arc of a circle centered on the articulation  5 . The front part of this aperture  17  is occupied by an elastomeric material  18 , such as rubber, leaving free a hole  19  in which the stud  16  engages during closure of the collar. In forward flexion, the elastic material  18  gives the collar greater flexibility. 
     The aperture  17  could be replaced by a hole corresponding to the hole  19 . 
     Multiple variations and modifications are possible in the embodiments of the invention described here. Although certain illustrative embodiments of the invention have been shown and described here, a wide range of modifications, changes, and substitutions is contemplated in the foregoing disclosure. In some instances, some features of the present invention may be employed without a corresponding use of the other features. Accordingly, it is appropriate that the foregoing descriptions be construed broadly and understood as being given by way of illustration and example only, the spirit and scope of the invention being limited only by the appended claims.