Patent Publication Number: US-7219444-B2

Title: Boot liner with ankle and heel volume control

Description:
FIELD OF THE INVENTION 
   The present invention relates to snowboard boots, and more particularly to lacing systems of snowboard boot liners. 
   BACKGROUND OF THE INVENTION 
   Snowboarding is a popular winter sport in which a snowboarder stands atop a snowboard and maneuvers the board over the snow, propelled by gravity. The snowboarder wears boots that are removably attached to the board, with the snowboarder&#39;s feet angled with respect to the longitudinal axis of the board. Often the rider&#39;s feet are substantially perpendicular to the board axis. The snowboard is controlled by weight transfer and foot movement, both lateral and longitudinal. 
   A primary skill that must be mastered in snowboarding is carving a path through the snow, rather than simply sliding or skidding over the top of the snow. The ability to carve provides the snowboarder with the most control of the direction and speed of the snowboard. In its simplest execution, a snowboarder carves a path through the snow by shifting his or her weight forward or backward, causing the snowboard to tilt or rotate about its longitudinal axis toward and away from its back side edge. As used herein, front side refers to the side or direction to which the snowboarder&#39;s toes are closest (toe side) and back side refers to the opposite side or direction (back side). 
   In order for a user to most effectively control the snowboard, the user&#39;s foot must be firmly gripped by the snowboard boot. It is particularly important that the user&#39;s heel be held firmly against shifting when, for example, leaning forward to carve a toe-side turn. Furthermore, snowboard boots typically have a stiff outer shell surrounding a softer inner liner. As the liner breaks down with continued use, it loses its effective grip of the heel and ankle. Furthermore, different users have differently shaped feet, making it difficult to make a boot that will ideally fit a wide range of users. Heel width and shape, for example, vary widely among riders. 
   Various boot designs attempt to solve these problems. Some ski boot designs involve pulley systems that leverage against the rigid plastic shell of the ski boots to drive the heel of a user against the ski boot. Snowboard boot designs that have attempted to solve this problem have applied tension to the liner at the front of the boot to decrease the circumference of the boot in the entire ankle and heel region. However, other snowboard and ski boots do not provide any means to conform the actual heel and ankle area of the boot to the heel and ankle of a user. Particularly, they do not provide any dynamic shaping or gripping at the sides of the heel. 
   Thus, it would be an advancement in the art to provide a snowboard boot that can dynamically control the volume of the heel of the boot in order to conform it to the heel of different users. It would be a further advancement in the art to provide a system that ensures that the heel area grips the heel of a user even as the liner breaks down from continued use. 
   SUMMARY OF THE INVENTION 
   The present invention provides a system for controlling the volume of the heel and ankle areas of footwear. It is particularly useful with snowboard boot liners that fit inside shells made of relatively stiff material. It includes a rear tensioning system that applies pressure directly at, or around, the heel of footwear shaped to receive a user&#39;s foot. The tensioning system may cooperate with a main closure or tensioning system, such as laces or the like, at the front of a boot to transfer tension from a front tensioning system to the rear tensioning system. 
   A control element, such as a tether, is secured to the liner near the instep and a channeling element, such as an overlay of material, is secured at, or near, the heel. A draw, such as a lace or other tensioning system, is secured to both the channeling element and the control element in order to draw them together. In some embodiments, the draw is a rear lace that winds through the channeling element and control element. One end of the rear lace may attach to part of the footwear in the heel region, proximate the sole. The rear lace may pass through a guide secured to the foot portion or to the channeling element, through an eyelet formed in the control element, and through another guide secured to the channeling element or foot portion. In some embodiments the guides are plastic tubes sized to receive the lace. The rear lace may then secure to the front tensioning system. In some embodiments, the front tensioning system is a front lace, in which case, the front lace may pass through an eyelet, or loop, secured to the rear lace. When the front lace is tightened, it pulls on the eyelet thereby drawing the channeling element and control element together and reducing the volume of the liner in the heel region. 
   The rear lace may extend up to another guide, such as a plastic tube, secured proximate the top of the footwear. The guide may allow the rear lace to engage the front tensioning system at a point where it can exert the greatest tensile force on the rear lace. For example, where the front tensioning system is a lace, the portion of the lace proximate the top of the footwear will typically be subject to greater tensile forces. 
   A second draw and a second control element are typically used and disposed in a manner substantially mirroring the disposition of the first draw and first control element. The channeling element is likewise substantially symmetrically shaped and has symmetrically placed guides to accommodate the second draw, which is typically a second rear lace. 
   In some embodiments, the rear tensioning system is tightenable independent of the front tensioning system. For example, a cord lock, such as might be used to close the opening of a bag, may be used to secure the rear lace. Alternatively, two rear laces could simply be knotted together once tensioned. Accordingly, the laces could be manually tightened and knotted as is done in traditional lacing systems. 
   The cord lock may secure to a latch attached to the footwear. The latch secures the lock when the cord is being tightened and allows a user to pull on the lace without needing to hold the lock still. The latch is typically a projection with lips formed on it. The lower lip is relatively stiff and secures the cord lock against movement when the rear lace is being tightened. The projection has a compliant upper lip which elastically deforms to allow an aperture in the cord lock to be passed over the projection. After the cord lock is in place, the upper lip springs back and resists removal of the cord lock. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
       FIG. 1  is a perspective view of a snowboard boot liner in accordance with the invention; 
       FIG. 2  is an exploded view of a rear tensioning system in accordance with the invention; 
       FIG. 3  is a rear view of tensioning and support structures in accordance with the invention; 
       FIG. 4  is a rear view of an alternative embodiment illustrating a rear tensioning system in accordance with the invention; and 
       FIG. 5  is partial side view of a latch in accordance with the invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIGS. 1 and 2 , a preferred embodiment of a snowboard boot liner  10  has a front  12  and a back  14  and is shaped like a boot having a sole  16  and a foot portion  18 . The sole is made of rubber, plastic, or other suitably resilient material known in the art and a foot portion  18  made of deformable material and shaped to receive the foot and lower leg of a user. The foot portion  18  has a midfoot portion  20  which covers the arch and ankle of a user, a heel portion  22 , which covers the heel of a user, and a lower leg portion  23 , which encircles the lower leg of a user. The present invention, although applied in this case to a boot liner  10 , could be used with any footwear made of compliant material. 
   A front opening  24  is formed in the foot portion  18  to facilitate donning of the liner  10 . A top opening  25  is located at the top of the lower leg portion  23 , encircles the leg of a user wearing the liner  10 , and likewise facilitates donning of the liner  10 . The front opening  24  is disposed toward the front  12 . Alternatively, a front opening  24  may be placed toward the back  14 , or on either side of the foot portion  18 . A front closure or tensioning system  26  serves to constrict the front opening  24 . The front tensioning system  26  comprises any tensioning system suitable for fastening footwear, such as a lever system having a locking toggle position, VELCRO™, or the like. In the illustrated embodiment, the front tensioning system  26  is a lacing system having a series of eyelets  30  arranged along the front opening  24  and a front lace  32  threaded through them. The eyelets  30  are hooks, grommets, loops of material, or any other structure suitable for lacing systems. 
   A rear tensioning system  34  is used in accordance with a preferred embodiment of the invention to control the volume of the heel portion  22 . The rear tensioning system  34  includes a channeling element  36  positioned proximate the heel portion  22 . The rear tensioning system  34  also includes a control element  38  secured to the midfoot portion. In the embodiment of  FIGS. 1 and 2 , the rear tensioning system  34  includes two control elements  38  secured opposite one another on either side of the midfoot portion  20 . The channeling element  36  and the control element  38 , or control elements  38 , are positioned at various locations on the heel portion  22  and midfoot portion  20 , such that they can be drawn together to constrict the heel portion  22  and midfoot portion  20  around the heel and rear ankle of a user. A rear tensioning system  34  includes a draw  40 . The draw  40  serves to pull the control element  38 , or control elements  38 , toward the channeling element  36 , or to pull the control elements  38  toward one another. 
   In the embodiment of  FIGS. 1 and 2 , the channeling element  36  is an overlay  42 . The overlay  42  covers part of the heel portion  22 . In some embodiments, the overlay  42  has one or more branches  44  extending from it secured to one or more tensioning straps  46 . The tensioning straps  46  are secured to the lace  32  and have eyelets  30  formed in them. In this manner, the tension of the laces will transfer to the channeling element  36 . The overlay  42  is typically constructed of a flexible and resilient material, such as Thermoplastic Polyurethane (TPU), or other suitable material. 
   In the embodiment of  FIGS. 1 and 2 , a control element  38  is a control tether  48  secured at one or more securement points  50 . The draw  40  secures to a pull point  52  on the control tether  48 . The securement points  50  and pull point  52  serve to direct the tension of the draw  40  along a line  54 , thereby controlling the volume shaping achieved by the rear tensioning system  34 . 
   The draw  40  is embodied as a rear lace  56 . In embodiments having two control elements  38 , a rear tensioning system  34  may have two rear laces  56 . In the preferred embodiment, a rear lace  56  has one end  58  secured to the sole  16  proximate the back  14 . Alternatively, the rear lace may be secured to the body of liner  10  or another component. The rear lace  56  passes through a guide  60 , which serves to direct the tension in the rear lace  56 . A guide  60  may also be embodied, for example, as a hole or channel formed in the channeling element  36 , a hook, a line of stitches, or any other suitable structure. 
   In the illustrated embodiment, a guide  60  is embodied as a tube  62  secured to the channeling element  36 , or secured by the channeling element  36  to the foot portion  18 . In some embodiments, the tube  62  is formed monolithically with the channeling element  36 . The guide  60  typically has a curvature  64  serving to convert a substantially horizontal pull into a substantially vertical pull exerted on the sole  16 . The tube  62 , is preferably made of plastic or any other suitable material providing adequate wear resistance, sufficient stiffness to avoid collapse, and reduced friction. 
   The rear lace  56  then passes through an eyelet  63  secured or formed at the pull point  46  of the control tether  42 . The eyelet  63  has various alternate embodiments such as a grommet, hook, or other such structure. The rear lace  56  then extends through another guide  66  secured to the overlay  42 . The guide  66  is typically a tube  68  made of plastic, or other suitable material. A guide  66  typically has a curvature  70  enabling it to change the direction of the forces resulting when a rear lace  56  is tensioned. For example, the guide  66  enables a substantially vertical pull applied to the rear lace  56  to be translated into a substantially horizontal pull exerted on the control tether  48 . The tube  68  is secured to the foot portion by the overlay  42 . Alternatively, it may be secured directly to the overlay  42  or the foot portion  18 . The tube  68  may also be formed monolithically or integrally with the overlay  42 . 
   Of course, embodiments other than those illustrated are possible. For example, in some embodiments, the end  58  of a lace  56  secures directly to a control tether  48 . In others, the end  58  secures to the overlay  42  directly. In embodiments having two laces  56 , the ends  58  may be secured to one another, such that the laces  56  pull against one another when tensioned. Alternatively, an integrated rear lace  56  may be used to achieve the same function as two laces  56  having their ends  58  secured to one another. In some embodiments, a portion of an integrated rear lace  56  extending across the heel portion may serve the function of the channeling element. The overlay  42  may then be omitted and the guides  66  may be embodied as hooks, tubes  68 , or the like, secured directly to the foot portion  18 . 
   Referring again to  FIG. 1 , the draw  40  then engages a lock  72 . The lock  72  serves to maintain tension in the draw  40  while the liner  10  is being worn. In the illustrated embodiment, the front lace  32  serves as the lock  72 . A rear lace  56  has an eyelet  74  formed or secured to it, with the front lace  32  passing therethrough. 
   Referring to  FIG. 3 , in some embodiments, the eyelet  74  is formed or secured near the end of a pull tether  76  secured to a lace  56 . A support  78  is typically secured to the foot portion  18 . The support  78  is constructed of a flexible yet relatively stiff material such as TPU. The support  78  typically secures to the foot portion  18  proximate the back  14 . In some embodiments, arms  80  are formed as part of the support  78 . Such arms  80  extend toward the front  12  and have apertures  82  formed therein with a pull tether  76  passing therethrough. The support  78  serves to maintain a pull tether  76  positioned proximate the front opening  24 , even when the front lace  32  is not tensioned. 
   In some embodiments, guides  84  are secured to the support  78 . The guides  84  may also be secured by the support  78  to the foot portion  18 , or be secured by some other means to the foot portion  18 . A guide  84  typically has a curvature  86 , enabling it to translate the substantially horizontal pull of a pull tether  76  into an upward pull. In the illustrated embodiment, the guide  84  is a tube  88 , but it may also be a hook  88 , or any suitable structure  88 . In some embodiments a tube  88 , or other such structure  88 , is formed monolithically with the support  78 . Support  78 , in some embodiments, is formed integrally with or otherwise joined to overlay  42 . 
   The guide  84  is typically positioned a distance  90  above the guide  66 . This serves to position the pull tether  76  closer to the top of the foot portion  18  and increase the tensile force exerted on the pull tether  76 . Typically, a lacing system is tightened by pulling the ends of laces positioned at the top of the shoe or boot. As the lace passes through each set of eyelets in the lacing system, the eyelets exert frictional forces on the lace, reducing the tensile force that can be exerted on subsequent eyelets. Thus, the portion of the front lace  32  at the top of the boot portion  18  will be under greatest tension. The pull tether  76  is therefore subject to greater tensile forces because it engages the front lace  32  near the top of the foot portion  18 . 
   The pull tether  76  secured to a lace  56  and a control tether  48  engaging that same lace  56  are typically positioned on opposite sides of the foot portion  18 . Thus, the laces  56  would cross one another, as shown proximate the back  14  in embodiments of the liner  10  having two laces  56 . 
   Referring to  FIG. 4 , a rear tensioning system may have various embodiments. For example, in  FIG. 4 , the lock  72  is a cord lock  92 . The cord lock  92  may be any structure known in the art to maintain tension in laces, lanyards, drawstrings or the like. In embodiments having two control elements  38  and two laces  56 , the lock  72  may also be formed by simply tying the two laces  56  into a knot. The lock  92 , of  FIG. 4 , is positioned at the top of the leg portion  23 , proximate the top opening  25 , to allow access when the liner is placed within a plastic outer shell. In the embodiment of  FIG. 4 , the guide  84  is straight, rather than having a curvature  84 . 
   The lock  72  typically secures to a latch  94  on the liner  10 . Alternatively, the lock  72  may secure to a latch  94  secured to a shell surrounding the liner. However, the lock  72  may simply be secured to the liner  10  by its engagement with the lace  56 , or laces  56 . Securing the lock  72  to the liner  10  or to an outer shell permits a user to readily pull the laces  56  there through without requiring a user to hold the lock  72  still. 
   Referring to  FIG. 5 , in some embodiments the latch  94  is a projection  96 . The end of the projection  96  has a first lip  98  extending downward and a second lip  100  extending upward. The first lip  98  is typically stiff, enabling it to restrain the cord lock  92  during tightening of the laces  56 . The second lip  100  is typically compliant. The cord lock  92  has an aperture  102  having a diameter  104  too small to fit over the undeformed first lip  98  and second lip  100 . However, the compliance of the second lip  100  enables the aperture to pass over the lips  98 , 100  by deforming the second lip  100 . Notwithstanding the compliance of the second lip  100 , the second lip  100  still serves to restrain the cord lock  92  when positioned over the projection  96  because some force is still required to deform it. The second lip  100  may point in lateral directions as well as upwards to accomplish its function. Likewise, the first lip  98  may point in various directions besides downward in order to provide retention of the cord lock  92 . 
   The latch  94  may have various other embodiments, including other systems used in the art to selectively secure structures. For example, the latch  94  could be embodied as one piece of a side release buckle system, with the other piece secured to the liner  10  or an outer shell. Furthermore, a latch  94  may also secure a cord lock  92  used to tighten a front lace  32 . For example, a projection  96  could be secured to the tongue of a boot liner. 
   While preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.