Abstract:
Shock-absorbing support pad to be positioned between a boot and a snowboard, or between the boot and a snowboard binding, and a snowboard binding incorporating such support pad. The support pad has at least two layers of material having different hardnesses. A first layer has a support surface for contacting the boot and it has a bonding surface opposite to the support surface. A second layer is joined to the bonding surface of the first layer. The hardness of the second layer is less than the hardness of the first layer.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of snowboarding and more particularly to a device for retaining a boot on a gliding board adapted for snowboarding. 
     2. Description of Background and Material Information 
     The practice of snowboarding is generally done with either rigid shell boots or flexible boots. 
     For flexible boots, certain retaining devices have at least one shock-absorbing support pad, generally located between a baseplate of the device and the boot when the latter is retained on the device. 
     The support pad is provided to improve the user&#39;s comfort and to absorb the impacts or short displacements of the boot with respect to the device. 
     It has been observed that certain support pad deteriorate very quickly when the device is used and, as a result, they no longer fulfill their shock-absorbing role. 
     It has also been observed that the support pad that resist a quick deterioration do not absorb the impacts or short displacements enough, and that these support pad do little to improve the user&#39;s comfort. 
     SUMMARY OF THE INVENTION 
     An object of the invention is to provide a support pad that improves the user&#39;s comfort and absorbs the impacts or short displacements of the boot with respect to the retaining device, i.e., the binding, while resisting the wear and abrasion caused by the boots. 
     Another object of the invention is to provide a retaining device having at least such a support pad. 
     A shock-absorbing support pad according to the invention is provided to be arranged between a boot and a board, or between the boot and a device for retaining a boot on the board, the board being adapted to snowboarding. 
     The support pad, according to the invention, has at least two layers of materials with a different hardness, a first layer which has a support surface provided to make contact with the boot and which has a bonding surface opposite to the support surface, and a second layer which is joined to the bonding surface from the first layer, the hardness of the second layer being less than the hardness of the first layer. This structure improves the user&#39;s comfort and absorbs the impacts or short displacements of the boot due to the second layer. Additionally, this structure offers a good resistance to the wear and abrasion caused by the boots due to the first layer. 
     According to a particular feature of the invention, the first layer and the second layer are glued together. 
     According to another feature of the invention, the first layer is made from a relatively flexible plastic material with a substantially continuous structure, and the second layer is made from a relatively flexible plastic material with a cell-type structure. 
     In addition to the foregoing, the invention also encompasses a device for retaining a boot on a gliding board adapted to snowboarding, the device comprising at least one shock-absorbing support pad provided to make contact with the boot, wherein the wedge comprises at least two layers of materials of a different hardness, a first layer which has a support surface provided to make contact with the boot and which has a bonding surface opposite to the support surface, and a second layer which is joined to the bonding surface of the first layer, the hardness of the second layer being less than the hardness of the first layer. 
     Further according to the invention, the support pad is arranged to contact a baseplate of the device, so that the first layer touches the sole of the boot when the latter is retained on the device. 
     Still further according to the invention, the first layer and the second layer are glued together, and the first layer is glued to the baseplate. 
     Still further according to the invention, the first layer of the support pad is made from a relatively flexible plastic material with a substantially continuous structure, and the second layer of the support pad is made from a relatively flexible material with a cell-type structure. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     Other characteristics and advantages of the invention will be better understood with the following description with reference to the attached drawings which show, by way of non-limiting examples, how the invention can be obtained, and in which: 
     FIG. 1 is a perspective view of a retaining device for a flexible boot, the device having two support pad; 
     FIG. 2 is a cross-section taken along the line II—II of FIG. 1 corresponding to a first embodiment; and 
     FIG. 3 is similar to FIG. 2 but corresponds to a second embodiment. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A retaining device or binding  1  according to the invention and shown in FIG. 1 is provided to retain, in a known manner, a boot (not shown) on a board  2 . The device  1  has a baseplate  3  provided to receive the sole of the boot, as well as a rear support element  4  allowing a rear support by contact with the boot upper at the rear of the lower part of the user&#39;s leg. The device  1  is affixed to the board  2  by a disk  5  and by means for retaining the disk  5  onto the board  2 . 
     A first embodiment of the invention is described with reference to FIG.  2 . 
     As known, the baseplate  3  has an upper surface  6  facing the sole of the boot when the latter is retained on the device  1 , as well as a lower surface  7  opposite to the upper surface  6 . The board  2  has a support surface  8  opposite to a gliding surface  9 , the surface  8  of the board  2  touching the lower surface  7  of the baseplate  3 . 
     A shock-absorbing support pad  10  is housed in a closed cavity  1  of the baseplate  3 , the cavity  11  having a bottom  12  and a peripheral edge  13 . The support pad  10  has a first layer  14  provided to make contact with the sole, as well as a second layer  15  located between the layer  14  and the bottom  12 . 
     A support surface  16  of the first layer  14  is upwardly exposed for contacting the sole of the boot when the latter is retained on the baseplate  3 . A bonding surface  17  of the layer  14 , opposite to the support surface  16  with respect to the thickness of the layer  14 , is joined to the second layer  15 . 
     Preferably, the bonding between the layers  14  and  15  is obtained by an adhesive, but any other technique could be used. 
     The first layer  14  is made from a relatively flexible material which resists well attrition, pulling, cutting, or other mechanical biases. It is preferably obtained from a flexible plastic material having a homogenous and continuous structure, as a polyurethane sheet, a rubber sheet or any suitable material. 
     For example, the layer  14  can measure between 1 and 2 mm thick and bends easily between the fingers when manipulated. Its thickness is reduced from 1% to 10% when it is subjected to a compression force which generates a stress between 50 and 100 N/cm 2 . 
     The second layer  15  is made from a flexible material which has good elastic deforming and shock-absorbing abilities. The flexible material can be a foam made from a plastic material with a cell-type structure, a rubber foam, or any other suitable material such as a fiber mat. 
     For example, the layer  15  can measure between 2 and 10 mm thick and bends easily between the fingers when manipulated. Its thickness is reduced from 30% to 50% when it is subjected to a compression force, which generates a stress between 50 and 100 N/cm 2 . 
     In any case, the second layer  15  has greater flexibility than the first layer  14 . 
     Preferably, the wedge  10  is retained in the cavity  11  by a retaining means constituted here by gluing. 
     A second embodiment of the invention is seen in FIG.  3 . 
     For convenience, the same reference numerals are used to designate the same elements or similar elements. 
     The support pad  10  is housed in a through cavity  18  of the baseplate  3  whose opening facing the board  2  is larger than the opening leading to the upper surface  6 . 
     The first layer  14  is pressed against a peripheral edge  19  of the cavity  18 . 
     The second layer  15  is arranged between the first layer  14  and the board  2 . 
     The materials used for implementing the second embodiment are similar to those of the first embodiment. 
     The respective shapes of the support pad  10  and the cavity  18  allow maintaining the support pad  10  in the cavity  18 . 
     However, it is possible to provide a complementary means for affixing such as gluing the support pad  10  to the peripheral inner surface edge  19  of the cavity  18  of the baseplate  3 . 
     Preferably for all embodiments, the support surface  16  of the support pad  10  projects slightly with respect to the upper surface  6  of the baseplate  3 . Thus, the contact between the sole and the support pad  10  is preferred with respect to a contact between the sole and the surface  6  of the baseplate  3 . 
     When the boot takes support on the device  1 , the thickness of the support pad  10  is reduced, essentially by compression of the second layer  15 . Inversely, when the boot is separated from the device  1 , the support pad  10  returns to its original shape due to the elasticity of the constitutive material of the second layer  15 . 
     As seen in FIG. 1, the baseplate  3  of the device  1  has a crescent-shaped support pad  10  located substantially at the metatarsal bones of the foot, as well as a crescent-shaped support pad  20  located substantially towards the heel of the foot. The shapes of the support pad  10 ,  20  improve foot stability and comfort during torsional biases of the user&#39;s leg. 
     The invention is not limited to the embodiments described herein, and includes all technical equivalents within the scope of the following claims. 
     In particular, the shapes of the wedges  10 ,  20  and the thicknesses of their materials can vary to allow selecting specific shock-absorbing values, for example. 
     The shapes of the cavities  11 ,  18  can also vary, and possibly be different from the shapes of the support pad  10 ,  20 . 
     The bonding surface  17  of the first layer  14  can be planar as in the first embodiment, curved inward as in the second embodiment, or have any suitable shape. 
     Furthermore, each support pad  10 ,  20  can have additional layers which, in this case, would be located between the second layer  15  and the bottom  12 , or between the second layer  15  and the surface  8  of the board  2 . 
     This application is based upon French Patent Application No. 97 12738, filed Oct. 3, 1997, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is hereby claimed under 35 USC 119.