Abstract:
A footwear article ( 1 ), for practicing a sport, in particular, motorcycling, includes a rigid body ( 2 ), for housing the foot of a user, running in an extension direction ( 8 ), a rigid upper ( 4 ), for housing the leg of a user and running essentially in an elevation direction ( 10 ), a joint ( 6 ), permitting the rotation of the upper with relation to the body in a transverse direction ( 12 ), stop elements for limiting the rotation of the upper ( 4 ) with relation to the body ( 2 ) in the transverse direction ( 12 ) within a range of rotation limits over 50 to 70 degrees, damping elements ( 14 ), generating a torque which opposes the approach of the first and second stop elements, the damping elements having an inactive state when the upper and the body move relative to each other within a normal rotation range of 30 to 50 degrees.

Description:
FIELD OF THE INVENTION 
     BACKGROUND OF THE INVENTION 
     The present invention relates to an item of footwear which is intended for sporting use. 
     It is particularly suitable for protecting a user who is participating in motor sports and more particularly motorcycling. However, it may also be found to be advantageous for use in snowboarding, mounting biking, jet-skiing or hiking, in particular. 
     WO-A-01 35781 describes an item of footwear of this type, and more particularly a motorcycle boot comprising:
         a first rigid shell which defines a body which is intended to receive the foot of a user and which extends in an extension direction,   a second rigid shell which defines an upper which is intended to receive the leg of the user and which extends substantially in an upright direction,   an articulation which connects the body and the upper, said articulation allowing the upper to rotate relative to the body in a transverse direction which is substantially perpendicular to the extension direction and the upright direction, in order to allow flexion of the foot of the user,   stop means comprising a first element which is connected to the body and a second element which is connected to the upper, one coming into contact with the other in order to limit the rotation of the upper relative to the body in the transverse direction within a maximum rotation range,   damping means which produce a couple in the transverse direction opposing the moving together of the first and second stop elements.       

     That item has been found to be strong and protects the user effectively. However, it is sometimes desirable to provide a simpler, lighter item which affords greater comfort in use. 
     Furthermore, U.S. Pat. No. 5,909,885 describes a roller boot which is provided with an energisation device which differs from WO-A-01 35781 in that
         the stop means comprise:
           first stop means which comprise a first element which is connected to the body and a second element which is connected to the upper, one coming into contact with the other in order to limit the rotation of the upper relative to the body in the transverse direction in a first rotation direction,   second stop means which comprise a first element which is connected to the body and a second element which is connected to the upper, one coming into contact with the other in order to limit the rotation of the upper relative to the body in the transverse direction in a second rotation direction counter to the first rotation direction,   
           the damping means comprise:
           first damping means which produce a couple in the transverse direction opposing the moving together of the first and second stop elements of the first stop means, and   second damping means which produce a couple in the transverse direction opposing the moving together of the first and second stop elements of the second stop means.   
               

     However, those features are intended to improve the efficacy of the skating and not the protection of the lower leg, in particular the ankle, of the user. 
     SUMMARY OF THE INVENTION 
     So that the item of footwear is comfortable whilst at the same time protecting the user effectively against any risk of injury, in accordance with the invention the maximum rotation range in the transverse direction extends over from 50 degrees to 70 degrees and the normal rotation range in the transverse direction extends over from 30 degrees to 50 degrees and is substantially centred relative to the maximum rotation range. 
     In this manner, the normal rotation range is extended enough for the user to be able to freely flex his ankle during normal use of the item of footwear. Although the remainder of the “angular travel” for stopping the rotational movement progressively before the risk of injury and the arrival at abutment may be reduced, it is found to be sufficient for a given number of sports which do not require extreme protection. 
     Advantageously, the damping means comprise a thin flexible plate which has a first end which is connected to one of the two shells and a second end which moves freely within the normal rotation range and which comes into abutment with the other shell between the normal rotation range and the maximum rotation range. 
     This construction is simple and provides good strength at moderate cost. 
     In accordance with another feature of the invention, the thin flexible plate is connected to said shell near the articulation. This construction provides the user with a high level of comfort. 
     The thin flexible plate preferably has a curved portion which extends around the articulation, which allows the thin flexible plate to be readily connected to the shell. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be appreciated even more clearly from the following description given with reference to the appended drawings, in which: 
         FIG. 1  shows a motorcycle boot in accordance with the invention in a rest position, 
         FIG. 2  shows the boot of  FIG. 1  in a flexion position, 
         FIG. 3  shows the boot of  FIG. 1  in an extension position, 
         FIG. 4  is a partial cross-section along the arrow indicated IV-IV in  FIG. 1  in a rest position, 
         FIG. 5  is a perspective view of a damping element according to the invention, 
         FIG. 6  shows a variant of the boot according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       FIGS. 1 to 4  illustrate a boot  1  comprising a body  2  which is intended to receive the foot of a user in the lower portion, an upper  4  which is intended to receive the leg of a user in the upper portion, an inner lining  3  which extends inside the upper  4  and the body  2 , an articulation device  6  which connects the upper  4  to the body  2  in the intermediate portion, stop means  32 ,  34  and damping means  14 . 
     The inner lining  3  is relatively flexible. It is advantageously produced, during conventional shoemaking, from leather or synthetic material and provides the user with comfort. The body  2  and the upper  4  in conjunction with the articulation device  6  ensure the protection of the user. The body  2  and the upper  4  each comprise a relatively rigid shell, which is advantageously produced from plastics material and which is intended to protect the lower limbs of the user. Those shells can be perforated locally. The body extends in an extension direction  8  which is substantially horizontal when the user places his foot on a horizontal surface whilst the upper extends in an upright direction  10  which is substantially vertical. 
     The extension direction  8  and the upright direction  10  define a centre plane P which is parallel with the plane of illustration of  FIGS. 1 to 3 . The boot  1  further has a transverse direction  12  which extends substantially perpendicularly to the extension direction  8  and the upright direction  10 . 
     The articulation device  6  brings about the rotation of the upper  4  relative to the body  2  in the transverse direction  12 . It comprises two articulation pivots  24 ,  26  which are arranged substantially symmetrically relative to the plane P and which extend in the transverse direction  12  through the body  2  and the upper  4 . 
     The stop means  32 ,  34  comprise flexion stop means  32  and extension stop means  34 . The flexion stop means  32  and the extension stop means  34  each comprise a first portion  32   a ,  34   a  which is connected to the body and a second portion  32   b ,  34   b  which is connected to the upper  4 , said first and second portions of the flexion and extension stop means coming into abutment with each other in order to stop the rotation of the upper  4  relative to the body  2  in the transverse direction  12  in terms of flexion and extension, respectively. 
     The damping means  14  are constituted by two thin resiliently deformable plates  16 ,  18  which are connected to the upper  4  and which each move inside a housing  28  which is provided in the body  2  and which is delimited by a flexion stop surface  20 , a pronation/supination stop surface  21  and an extension stop surface  22 . The housings  28  and in particular the flexion stop surface  20 , pronation/supination stop surface  21  and extension stop surface  22  thereof are arranged substantially symmetrically relative to the plane P. 
     The two thin deformable plates  16 ,  18  are integrated in a unitary damping element  30  which is of resiliently deformable material and which further comprises a connection element  36  which retains said thin deformable plates relative to the upper  4 . The damping element  30  is also substantially symmetrical relative to the centre plane P. 
     The thin deformable plates  16  extend in the direction of the articulation axis and substantially in the upright direction. They each comprise a free end  16   a ,  18   a  and an end  16   b ,  18   b  which is connected to the connection element  36 . The connection element  36  is substantially U-shaped comprising two branches  40   a ,  40   b  which extend substantially in the extension direction  8  and which are connected to each other by a base  42  which extends substantially in the transverse direction  12 . The base  42  includes a retention stud  38  which is introduced in the upper  4  in the extension direction  8 , whilst the branches  40   a ,  40   b  each terminate in a curved portion  44   a ,  44   b  which is substantially circular and which extends in the transverse direction  12  around the pivots  24 ,  26 , under the enlarged head of said pivots  24 ,  26 . The connection element  36  and the end  16   b ,  18   b  of the thin flexible plates which are connected to the curved portions  44   a ,  44   b  are thus completely retained relative to the upper  4  by means of the curved portions  44   a ,  44   b  and the retention stud  38 . Furthermore, the damping element  30  can readily be disassembled and replaced by the curved portions  44   a ,  44   b  being deformed. In order to prevent inadvertent disassembly and in order to protect it, the thin plates  16 ,  18  are advantageously retained in the housings  28  behind a cover (not illustrated). 
     As illustrated in  FIGS. 1 and 2 , in the event of a flexion movement of the ankle of a user about the transverse direction  12 , the upper  4  pivots about the pivots  24 ,  26 , the thin plates  16 ,  18  move freely in the housings  28  until the free end  16   a ,  18   a  of the thin plates  16 ,  18  come into contact with the flexion stop surfaces  20  of the housings  28 . The thin plates  16 ,  18  then become deformed progressively in terms of flexion in the transverse direction  12  until the two portions  32   a ,  32   b  of the flexion stop means  32  come into contact with each other. 
     As indicated in  FIG. 2 , the magnitude α 1  of the free flexion movement allowed by the articulation device  6 , without any deformation of the thin flexible plates  16 ,  18 , is approximately 20 degrees relative to the initial position illustrated in  FIG. 1 . Subsequently, over a maximum flexion magnitude of approximately 5 additional degrees, the thin flexible plates  16 ,  18 , becoming deformed in terms of flexion, oppose the continuation of the flexion movement and thus damp any impact against the flexion stop means  32 . 
     Conversely, as illustrated in  FIGS. 1 and 3 , during an extension movement of the ankle of a user about the transverse direction  12 , the upper  4  pivots about the pivots  24 ,  26 , the thin plates  16 ,  18  move freely in the housings  28  until the free end  16   a ,  18   a  of the thin plates  16 ,  18  come into contact with the extension stop surfaces  22  of the housings  28 . The thin plates  16 ,  18  then become deformed progressively in terms of flexion in the transverse direction  12  until the two portions  34   a ,  34   b  of the extension stop means  34  come into contact with each other. 
     As indicated in  FIG. 3 , the magnitude α 2  of the free extension movement allowed by the articulation device  6  is approximately 25 degrees relative to the initial position illustrated in  FIG. 1 . Subsequently, over a maximum extension magnitude of approximately 5 additional degrees, the thin flexible plates  16 ,  18 , becoming deformed in terms of flexion, oppose the continuation of the extension movement and thus damp any impact against the extension stop means  34 . 
     The extent of normal rotation allowing the user to move his ankle without any effort in the transverse direction  12  is therefore substantially 45 degrees. It is advantageously from 30 to 50 degrees, whilst the extent of maximum rotation between the stop position against the flexion stop means  32  and the stop position against the extension stop means  34  is substantially centred relative to the normal rotation and is advantageously from 50 degrees to 70 degrees. Furthermore, the thin flexible plates  16 ,  18  advantageously act over a rotation range of from 5 degrees to 20 degrees, both during the flexion movement and during the extension movement of the ankle. 
     Furthermore, the construction illustrated in  FIGS. 1 to 4  allows the upper  4  to rotate relative to the body  2  in the extension direction  8  in order to allow pronation/supination of the ankle. For this purpose, as illustrated in  FIG. 4  (the partial cross-section not illustrated is substantially symmetrical), the passages  46  which are provided in the body  2  and through which the pivots extend are of oblong form and extend in the upright direction  10 . Slight translation movements in the upright direction  10  between the upper  4  and the body  2  are also possible in order to follow the movement of the malleolus of the user. 
     In the event of a pronation/supination movement of the ankle of a user about the extension direction  8 , the pivots  24 ,  26  slide freely in the oblong holes  46  until the free end  16   a ,  18   a  of the thin plates  16 ,  18  come into contact with the pronation/supination stop surfaces  21  of the housings  28 . The thin plates  16 ,  18  are then progressively compressed in order to damp the movement until the pivots  24 ,  26  reach a stop position in the oblong holes  46 . 
     The magnitude of each of the free pronation and supination movements is approximately 10 degrees (that is to say, a free pronation/supination magnitude of approximately 20 degrees) and it is further advantageously possible to carry out a rotation in the extension direction of approximately 5 degrees before reaching the stop position in that articulation direction. 
       FIG. 6  illustrates a boot  1 ′ which substantially differs from the construction illustrated in  FIGS. 1 to 4  in that the upper  4  can pivot only in the transverse direction and in that it comprises only a single thin flexible plate  16 ′. 
     The absence of translation and rotation in the upright direction  10  and rotation in the extension direction  8  is because circular holes are provided in place of oblong holes in the body  2 , through which holes the pivots  24  extend. 
     It is not necessary to provide a second thin flexible plate since the thin flexible plate  16 ′ has adequate characteristics.