Patent Publication Number: US-10757999-B2

Title: Ski boot provided with an improved ski-walk selection mechanism

Description:
FIELD OF THE INVENTION 
     The present invention relates to a ski boot provided with an improved ski-walk selection mechanism. 
     STATE OF THE ART 
     The mountaineering or Alpine ski boots must allow the skier to pass from skiing to walking configuration alternatively, in an easy and comfortable way. 
     In order to pass form skiing to walking configuration, known ski mountaineering or Alpine boots comprise an upper part or cuff of the boot, suitable for enclosing the lower part of the skier&#39;s leg, which is hinged to a lower part of shell of the boot, which is suitable for enclosing the user&#39;s foot. 
     In particular, the rotation of the cuff with respect to the shell grants a better and more comfortable walking, since it follows the natural rotation of the ankle. 
     Such rotation of the cuff can be blocked by fixing the cuff to the shell, reversibly, in order to grant a correct and precise skiing. 
     The passage form the walking to the skiing configuration should be as much rapid and easy as possible since the skier, during ski mountaineering, has to pass from the two configurations a lot of times, according to the passage/path to afford. 
     PRESENTATION OF THE INVENTION 
     The main solutions of the prior art provide that the cuff is hinged to the shell and that its rotation movement is guided by at least one rod. 
     The rod in correspondence of a first fixed end is hinged in turn to the shell, while at a second free end, it slides inside a guide fixed to the cuff. 
     In the walking configuration, the free end of the rod can slide within the guide fixed to the cuff; moreover in the walking configuration the rod can rotate around the first end so as to follow the rotation of the cuff. In the skiing configuration, the free end of the rod is fixed to the guide and then to the cuff. 
     The closure or blocking of the rod may be realised by means of a pin which enters a hole positioned on the rod. 
     Prior art solutions have a lot of drawbacks. 
     In fact, in the skiing configuration there is always a certain resistance to the rotation of the cuff due to the fact that the free end of the locking rod rubs against its seat/portion of the cuff adapted to lodge it/drive it. 
     In other words, the rod tends to get stuck inside the guide thus making the walk particularly tiring. The problem is further amplified due to the low operating temperature and snow/ice that, during use, further tends to fit between the rod and the related guidance making it increasingly difficult relative displacement between them. 
     Also, the type of driving of the cuff adopted by the known solutions imposes severe limitations on placements between the hinges of reciprocal connection of the cuff to the cuff and the anchorages of the guide rod. These geometric limits are used to limit only partially the problem of the sticking of the cuff but, on the other hand, create strong constraints to the overall aesthetics and functionality of the boot. 
     Moreover, also in the skiing position, the known solutions do never guarantee an adequate stiffness, for example comparable to that obtainable by an equivalent ski boot, in particular with the cuff of the fixed type or non-rotatable with respect to the cuff. 
     In fact, the shape coupling between the pin/peg and the respective seat is inevitably free type and thus implies the presence of a clearance, albeit limited. 
     Moreover, if there were no clearance, the locking operation by the user becomes anything but convenient, since the pin would be from time to time stuck in its seat. The clearance, even if limited in coupling shaft/bore, results in a movement forwards and backwards of the shank with respect to the hull in the locking configuration, i.e. of skiing. Besides, this clearance also results in an annoying clicking sound every time, shifting weight forward or backward while skiing and/or changes of direction, there is a corresponding shift of the cuff. 
     This clearance reduces the stiffness of the boot and it certainly reduces the precision of skiing in that the user feels such ‘clearance’ or ‘play’ certainly not present in ski boots without the movement of the cuff (e.g. Alpine ski boots). 
     In summary, the solutions of ski boots of the prior art have excessive resistance to the movement of rotation of the cuff during walking, and excessive clearance of the same cuff during skiing. 
     In yet other words, the walk is never easy because restrained, and the ski is never as precise as that obtained with a corresponding ski boot, due to the movement of the cuff with respect to the shell even in the closed configuration/locking. 
     It should be observed that the two requirements, namely the ease of walking and precision of skiing, are often antithetical to the practicality of use: in fact rigid and precise mechanisms of closure, if on the one hand stiffen the structure of the boot, on the other are not very easy to operate by the user. 
     The convenience of operating is never to be neglected since during an excursion in touring the user must be able to lock/unlock mechanism of ski-walk even dozens of times an hour, without ever having to take off the gloves and often without even stop altogether. 
     The solution/purpose of the present invention is to provide a ski mountaineering boot that solves the drawbacks mentioned with reference to the known art. 
     These drawbacks and limitations are solved by a ski boot in accordance with claim  1 . 
     Other embodiments of the boot according to the invention are described in the subsequent claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
       Further characteristics and advantages of the present invention will be better understood from the following description of its preferred and non-limiting embodiment, in which: 
         FIG. 1  shows a lateral section view of a ski boot according to an embodiment of the present invention, in a walking configuration, wherein the cuff is in the forward rotation position; 
         FIG. 2  shows a lateral section view of the ski boot of  FIG. 1 , in a walking configuration, wherein the cuff is in the rearward rotation position; 
         FIG. 3  shows a lateral section view of the ski boot of  FIG. 1 , in a ski configuration, wherein the cuff is blocked in rotation; 
         FIG. 4  shows a perspective view of a component of the ski boot of  FIG. 1 ; 
         FIG. 5  shows a lateral section view of a ski boot according to another embodiment of the present invention, in a walking configuration; 
         FIG. 6  shows a lateral section view of the ski boot of  FIG. 5 , in a ski configuration, wherein the cuff is blocked in rotation. 
     
    
    
     The elements or parts of elements in common between the embodiments described below will be indicated with the same reference numerals. 
     DETAILED DESCRIPTION 
     With reference to above listed figures, with reference numeral  4  it is indicated a ski boot comprising a lower part or shell  8 , suitable for enclosing the user&#39;s foot and an upper part or cuff  12 , suitable for enclosing the lower part of the skier&#39;s leg. Please note that the definition of ski boot should be considered in a general manner and not restrictive: therefore with the term ‘ski boot’ it is indicated a mountaineering ski boot, an Alpine ski boot or also a Telemark ski boot. Therefore the scope of protection of the present invention is not limited to the specific type of ski boot. 
     Moreover, please note that the definitions of the shell and of the cuff should be considered in a general manner and not restrictive: the present invention does not present any type of limitation in respect of shapes, sizes, materials, type of cuff and shell, and therefore fall in the invention also types of cuff and shell which at least partially embrace the foot and the lower part of the leg, namely the shank of the skier. The cuff  12  is hinged to the shell  8  so as to rotate relative to the shell  8  around hinges  16  defining a rotation axis X-X, forward, toward a tip  20  of the boot  4 , and backwards toward a heel  22  of the boot  4 . 
     The type of hinge  16  can be varied and, preferably, there is provided a pair of hinges  16  arranged on opposite sides with respect to the cuff  12 . 
     Preferably, the hinges  16  identify an axis of rotation X-X horizontal, i.e. parallel to a sole  24  of the boot  4 . 
     The boot  4  comprises fastening means  28  suitable for selectively locking and/or unlocking the rotation of the cuff  12  with respect to the shell  8  depending on whether the user wants to switch from a skiing configuration to a walking configuration, respectively. Advantageously the fastening means  28  comprise a slider interposed between the cuff  12  and the shell  8 , wherein said slider  32  is fixed in rotation to the cuff  12  and it comprises first and second end stops  36 , 40 , placed at opposite sides of the slider  32 . 
     The slider  32  is movable with respect to the cuff  12  in order to move from the unlock or walking configuration, wherein the first and second end stops  36 , 40  do not interfere with the rotation of the cuff  12  with respect to the shell  8 , to the lock or ski configuration, wherein the first and second end stops  36 , 40  are configured so that, at the same time, abut against respective first and second abutment  44 , 48  of the shell  8 . 
     According to possible embodiments, the slider  32  is movable in translation and/or in rotation with respect to the cuff  12 . 
     In particular, first abutment  44  blocks the forward rotation of the cuff  12  with respect to the shell  8  and second abutment  48  blocks the backward rotation of the cuff  12  with respect to the shell  8 . 
     The slider  32  is configured so that, in said blocking configuration, it is compressed between said first and second abutment  44 , 48  of the shell  8 , in order to avoid any clearance (play, movement) in rotation between the cuff  12  and the shell  8 . 
     According to an embodiment, the first end stop  36  of the slider  32  comprise a couple of lugs  52  which are at least partially countershaped with respect to a correspondent edge  56  of the shell  8 . The lugs  52  act as first end stops  36  of the slider  32 . 
     According to a possible embodiment, the second end stop  40  of the slider  32  comprises a tooth  60  which is at least partially countershaped with respect to a correspondent boss  64  of the shell  8 . The boss  64  acts as second abutment  48  of the shell  8 . 
     Preferably the slider  32  is countershaped with respect to a bottom portion  68  of the shell  8 , in order to partially wrap said bottom portion  68 . 
     For example, the slider  32  is connected with a leverage  72  to the cuff  12  in order to urge the slider  32  from the ski to the walking configuration and vice versa, said linkage  72  being positioned, preferably, in a rear part of the cuff  12 , facing the heel  22  of the ski boot  4  and having a gripping portion  76  for a user. 
     According to an embodiment, the slider  32  and the cuff  12  have corresponding shapes or, in other words, are at least partially countershaped. In this way, there is a larger contact zone/surface area for the transfer of load and preload between matching components of the boot. 
     Preferably, the slider  32  is connected to the cuff  12  by means of a prismatic coupling. 
     According to an embodiment said prismatic coupling comprises a slot  80  and a coupling element  84  that engages in the slot  80 . For example the coupling element  84  comprises a fastening component and/or linear guide that engages in the slot  80 . 
     Said coupling element  84  may be a fastening component, which secures the slider  32  to the inside of the cuff, and/or a linear guide which enables the slider  32  to track correctly, guiding it through its range of travel. 
     According to an embodiment, the cuff  12  comprises closure means  88  for opposite flaps  92  of the cuff  12 , wherein said closure means  88  are operatively connected to the movement of the slider  32  so as to tighten the closure means  88  in the configuration of skiing and to open or loosen the flaps  92  of the shell  8  in the configuration for walking. 
     For example said closure means  88  are operatively connected to the slider  32  by means of cables and/or mechanical linkage  100 . 
     Thanks to the connection between the closure means  88  and the slider  32  it is possible, in a unique movement, both closing the closure means and blocking the rotation of the cuff  12  (in the so called ski configuration) and opening the closure means and allowing the rotation of the cuff (in the so called walking configuration). 
     The “Knee joint” design of the leverage  72  in combination with the slider  32  and with the end stops  36 , 40  provides ultimate leverage/mechanical advantage to close the system: tensioning the closure means  88  (upper buckles and power strap) while simultaneously applying preload to the locking ski mode system. There is also almost no loss of applied tension when closing the system because of the minimal travel of the pivot points of the leverage and linkage beyond the “dead point” of the three corresponding pivots of the closure system: the user retains almost all of the force required to close the system within the closure means/buckle and power strap tension. 
     As can be appreciated from the description, the mountaineering ski boot according to the invention allows to overcome the drawbacks presented in the prior art. 
     In particular, in the configuration of opening or unlocking, the rotation of the cuff with respect to the shell does not encounter any resistance noticeable by the user, since the cuff does not encounter obstacles to rotation, in either direction of cuff rotation. 
     Also the locking of the cuff with respect to the shell is extremely rigid and does not provide for any clearance that can also allow small movements of the cuff with respect to the shell. 
     In fact, the solution of the present invention includes the presence of two constraints unilateral, distinct and opposite each other, so as to stop, each, a direction of rotation of the cuff with respect to the shell. 
     The two constraints (end stops  36 / 40 ) are formed on opposite sides of the same slider, which is integral in rotation with the cuff and sliding in translation with respect to the latter, in the passage from the configuration of walking to that of skiing. 
     In fact the slider  32  forces the cuff to rotate forward against the end stops  36  on the shell  8  that represent the end of the forward stroke to the rotation of the cuff. 
     Furthermore, the same slider represents a block or limit the rearward rotation of the cuff with respect to the shell (interface/contact between  40 , 60  and  48 , 64 ). 
     As seen, in the closed or ski configuration the slider is in a state of compression so as to prevent any type of clearance or movement that can reduce the feeling of stiffness and precision from the user. 
     In particular, the present solution applies a preloaded connection on the components of the ski boot to provide even more rigidity in the interface between the cuff and shell, creating a progressive forward flex of the ski boot. This is achieved by compressing interacting/interlocking surfaces (end stops) the system presses itself together before any forward flex in introduced thus when the boot is flexed forward. The boot responds with a “progressive flex” because of immediate contact. Of course this preloaded design also compensates for clearance (play) between the components of this system (for instance tolerance&#39;s in the manufacturing process). 
     In this way there is no possibility of clearance or slack of the cuff, since any rotation/movement of the leg portion is prevented by the locking means. 
     This architecture gives a high rigidity to the structure of the boot entirely comparable with respect to that of the corresponding Alpine/ski boot with a fixed cuff. Therefore the skier, in the closed or locking configuration, has the feeling of using a ski boot since he feels high rigidity and precision; also the skier does not receive any feeling of clearance or slack and not hear any noise due to contact between parts coupled together, as is the case in the solutions of the known art. 
     Furthermore, the boot according to the present invention is extremely easy to use since the locking/unlocking is done with a simple movement of the actuating lever  76 . 
     The mechanism for locking and unlocking  72 , 76  is extremely reliable and easy to use: it can be easily and repeatedly operated by the user even when wearing gloves. 
     Moreover, thanks to the solution of the present invention, there are no constraints for the positioning of the hinges  16  of the cuff  12  with respect to the shell  8 : in this way the designer has more freedom of design. 
     Furthermore, the locking mechanism is displaced in a position protected by accidental impacts as it is located in the upper part of the boot, well above the hinges  16 . 
     One skilled in the art, in order to satisfy contingent and specific needs, may make numerous modifications and variations to the boots described above, all however contained within the scope of the invention as defined by the following claims.