Patent Publication Number: US-6663118-B1

Title: Snowboard interface with an upper portion that translates and rotates relative to a lower portion

Description:
BACKGROUND OF THE INVENTION 
     The present invention is directed to snowboard devices and, more particularly, to a snowboard boot, binding or other rider interface with an upper portion, such as a leg interface, that translates and rotates relative to a lower portion, such as a foot interface. 
     Snowboarders usually stand on the snowboard facing generally perpendicular to the longitudinal axis of the snowboard. To accomplish various maneuvers on the snowboard, the snowboarder must often shift his or her center of gravity forward or rearward in the long direction of the snowboard. This usually requires the snowboarder to be able to pivot his or her legs from side to side around the ankle. Various schemes are known to allow snowboarders to pivot their legs sideways. For example, DE 3,622,746 shows a binding with upper and lower sections that pivot around a longitudinal axis of the binding. U.S. Pat. No. 5,401,041 shows a boot with an upper leg section, a lower heel section and a pivot coupling between the upper leg section and the lower heel section, wherein the upper leg section pivots relative to the lower heel section around a longitudinal axis of the boot. Finally, U.S. Pat. No. 5,771,609 shows a boot similar to the boot shown in U.S. Pat. No. 5,401,041 but with the upper leg section and the lower heel section being formed as an insert between flexible inner and outer linings. 
     The applicant discovered that boots that pivot around a single fixed axis do not really accommodate the anatomical motion required for effective weight transfer on the snowboard. That is because rolling of the heel often accompanies articulation of the ankle during snowboard maneuvers, thus resulting in a more complex overall motion of the leg. Thus, there is a need to make a snowboard boot that accommodates such motion. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a snowboard interface that more closely accommodates the anatomical motion required to articulate the legs from side to side relative to the snowboard. In one embodiment of the present invention, a snowboard interface has an upper interface and a lower interface, wherein the upper interface rotates and translates relative to the lower interface. More specifically, the snowboard interface includes a foot interface, a leg interface and a coupling mechanism for coupling the leg interface to the foot interface so that the leg interface translates sideways and rotates sideways relative to the foot interface. In an even more specific embodiment, the coupling mechanism includes a leg coupling member coupled to the leg interface and a foot coupling member coupled to the foot interface. The leg coupling member moves relative to the foot coupling member, and a guide mechanism is provided for guiding the movement of the leg coupling member relative to the foot coupling member so that the leg coupling member translates and rotates relative to the foot coupling member. 
     In one form of the guide mechanism, a guide surface is disposed on one of the leg coupling member and the foot coupling member, and an outer peripheral surface is disposed on the other one of the leg coupling member and the foot coupling member so that the outer peripheral surface rolls on the guide surface when the leg coupling member moves relative to the foot coupling member. As a result, a pivot location follows the area of contact between the guide surface and the outer peripheral surface. 
     In another form of the guide mechanism, a first guide projection extends from one of the leg coupling member and the foot coupling member and a first slot is formed in the other one of the leg coupling member and the foot coupling member, wherein the first guide projection extends into the first slot. To provide additional variation on the movement of the leg coupling member relative to the foot coupling member, the first slot may have a varying width. To fine tune the movement of the leg coupling member relative to the foot coupling member, a second guide projection may extend from one of the leg coupling member and the foot coupling member and a second slot may be formed in the other one of the leg coupling member and the foot coupling member, wherein the second guide projection extends into the second slot. The first guide projection and the first slot cooperate with the second guide projection and the second slot to provide a compound motion of the leg interface relative to the foot interface. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of a particular embodiment of a snowboard boot according to the present invention; 
     FIG. 2 is a top view of a particular embodiment of a heel cup according to the present invention; 
     FIG. 3 is a side cross-sectional view of the rear portion of the snowboard boot shown in FIG. 1; 
     FIG. 4 is a rear view of a particular embodiment of a vertical position fixing mechanism according to the present invention; 
     FIG. 5 is an exploded view of a particular embodiment of a coupling mechanism according to the present invention; 
     FIGS.  6 (A)- 6 (C) are front views showing the operation of the coupling mechanism shown in FIG. 5; 
     FIG. 7 is an exploded view of another embodiment of a coupling mechanism according to the present invention; and 
     FIGS.  8 (A)- 8 (D) are front views showing the operation of the coupling mechanism shown in FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     FIG. 1 is a side view of a particular embodiment of a snowboard interface according to the present invention in the form of a snowboard boot. As shown in FIG. 1, the snowboard boot is made up of a sole portion  1 , a toe portion  2 , a lower interface, for example, a foot interface such as a heel portion  3 , and a upper interface, for example, a leg interface such an a leg portion  4 . In this embodiment, the boot sole  1  is equipped with a liner (not shown) molded from a hard resin. A stiff heel cup  5  makes up a portion of the heel portion  3 , either integrally with or independently from the liner in the sole portion  1 . Nylon 66® or another such material may be used for the stiff heel cup  5 . Heel cup  5  shares the curved shape of the heel portion  3 . If desired, heel cup  5  can be molded as a riser portion that rises continuously to the portion extending over the boot sole  1 . Heel cup  5  is molded such that it is exposed on the outside of the boot, but it can also be molded such that it is on the inside and cannot be seen. A stiff leg component  6  forms part of the leg portion  4  above the heel cup  5 . A cut-out  15  is formed over the center line of a covering  16  formed of a flexible material so that the leg portion  4  may move in a fore and aft direction relative to heel portion  3  as well as side to side relative to heel portion  3 . 
     FIG. 2 is a top view of heel cup  5 . Heel cup  5  comprises a heel cup bottom  21  with an opening  20 , a heel cup heel component  22  (FIG.  1 ), heel cup bottom extensions  23  that extend forward at the left and right positions from the heel cup bottom  21 , and heel cup side components  24  that extend forward at the left and right positions from the heel cup heel component  22  and that curves slightly as it continues to the heel cup bottom  21 . A heel cup vertical extension  25  extends upwardly from heel cup heel component  22 , and a heel cup guide portion  26  with side guide walls  27  and a vertical slot  28  extends arcuately upwardly from heel cup vertical extension  25 . 
     FIG. 3 is a side cross-sectional view of the rear portion of the snowboard boot showing how heel cup  5  interacts with a coupling mechanism  50  that fixes a vertical position of leg portion  4  relative to heel portion  3  and that allows leg portion  4  to simultaneously translate and rotate relative to heel portion  3 . In other words, leg portion  4  pivot sideways around a rear pivot location that varies as the leg portion pivots. FIG. 4 is a partial rear view of the snowboard boot, and FIG. 5 is an exploded view of coupling mechanism  50 . 
     Coupling mechanism  50  includes a leg coupling member  54  and a foot or heel coupling member  62 . Leg coupling member  54  is coupled to the stiff leg portion  6  (and hence leg portion  4 ) through bolts  58  and nuts  60 . Foot coupling member  62  is coupled to heel cup guide portion  26  (an hence heel portion  3 ) through a position fixing pin or bolt  70  that passes through slot  28  at approximately the longitudinal median plane P of the boot, a nut  74 , a release lever  78  and a position fixing plate  80 . Leg coupling member  54  is rotatably mounted around bolt  70  through a bushing  82  fitted in an arcuate slot  83  (FIG. 5) so that leg coupling member  54  pivots relative to foot coupling member  62 . 
     As shown in FIGS. 3 and 4, heel cup guide portion  26  includes a generally spherically-shaped concave front surface  84  that slidably contacts a complementary convex rear surface of foot coupling member  62  and a generally spherically-shaped convex rear surface  88  with serrations  90  that mesh with a complementary serrated surface  92  on position fixing plate  80 . Leg coupling member  54  is rotatably sandwiched between foot coupling member  62  and nut  74 . Position fixing plate  80  has a generally horizontal concave recess  96  that slidably contacts a cam surface  100  of release lever  78 . Bolt  70  includes a spherical head  104  with an axle  108  that is fitted within ears  112  of release lever  78 . 
     Rotation of release lever  78  to the position shown in FIG. 3 causes the effective length of bolt  70  to shorten as a result of the camming action between cam surface  100  and concave recess  96 . This causes nut  74 , bushing  82 , foot coupling member  62 , heel cup guide portion  26  and position fixing plate  80  to be securely clamped together in the vertical position fixed by the serrated surfaces  90  and  92 . Thus, serrations  90  and  92  fix the vertical position of leg coupling member  54 , and hence leg portion  4 , relative to heel portion  3 , while bushing  82  allows leg coupling member  54  to rotate around bolt  70 . When release lever  78  is rotated counterclockwise, the camming action between cam surface  100  and concave surface  96  causes the effective length of bolt  70  to increase, thus allowing position fixing plate  80  to disengage from the serrated concave surface  88 . This, in turn, allows foot coupling member  62  and position fixing plate  80  to slide along concave surface  84  and convex surface  88 , respectively, so that leg coupling member  54  orbits around an imaginary axis O to produce the fore and aft movement of leg portion  4 . 
     As shown more specifically in FIGS.  5  and  6 (A)- 6 (C), leg coupling member  54  has a generally arcuate undulating outer peripheral surface  110  that meshes with a generally horizontal undulating guide surface  114  formed as a ledge on foot coupling member  62 . Additionally, slot  83  has an arcuate shape disposed asymmetrically relative to a longitudinal median plane P of the boot. As a result, outer peripheral surface  110  rolls on guide surface  114  so that leg coupling member  54  pivots around a location on a pivot axis (X) defined by the area of contact between outer peripheral surface  110  and guide surface  114 . It should be readily apparent that the pivot location, and therefore pivot axis (X), constantly moves in a horizontal direction as leg coupling member  54  pivots, which is much different from any of the prior art boots discussed previously. 
     In this embodiment, the asymmetrical slot  83  cooperates with bolt  70 , which functions as a guide projection extending from foot coupling member  62 , to limit pivoting of leg coupling member  54  to a counterclockwise direction as shown in FIGS.  6 (A)- 6 (C). A side wall  118  (FIG. 5) on vertical extension  26  also inhibits clockwise pivoting of leg coupling member  54 . Of course, side wall  118  can be omitted and slot  83  can be symmetrical or otherwise shaped to allow both clockwise and counterclockwise pivoting of leg coupling member  54  if desired for a particular application. The coupling mechanism  50  in this embodiment has particular usefulness in a left side boot, although it could be used in a right side boot depending upon the application. 
     FIG. 7 is an exploded view of a coupling mechanism  150  according to the present invention, and FIGS.  8 (A)- 8 (D) are front views showing the operation of the coupling mechanism  150 . Items that are the same as the first embodiment are numbered the same. 
     In this embodiment, coupling mechanism  150  is structured so that a leg coupling member  154  pivots in a clockwise direction. Thus, in contrast to the first embodiment, vertical extension  25  includes a shoulder  118 ′ to inhibit counterclockwise pivoting of leg coupling member  154 . A leg coupling member  154  includes a variable width first slot  170  wherein a first end  174  of first slot  170  is wider than a second end  178  of first slot  170 . First slot  170  also is asymmetrical relative to the median plane P of the boot as shown in FIG.  8 (A), and first slot  170  cooperates with bolt  70 , which functions as a first guide projection extending from foot coupling member  162 , in a manner described below to produce the desired pivoting effect of leg coupling member  154 . Leg coupling member  154  also includes a second slot  182  that is generally symmetrical relative to the longitudinal median plane of the boot. Second slot  182  cooperates with a second guide projection  186  screwed into a threaded opening  187  and extending from foot coupling member  162  offset from the longitudinal median plane of the boot, as well as first slot  182  and first guide projection (bolt)  70 , to produce the desired pivoting effect of leg coupling member  154 . 
     As shown in FIGS.  8 (A)- 8 (D), the pivoting action of leg coupling member  154  is much more complicated than the simple rolling action of leg coupling member  54  in the first embodiment. Initially, first guide projection (bolt)  70  is located at the narrower end of slot  170 , and second guide projection  186  is located at the right end of slot  182 . When a pivoting force directed to the right in FIG.  8 (A) is applied to leg coupling member  154 , slot  170  moves to the right until first guide projection (bolt)  70  is disposed at the wide end  174  of slot  170  and second guide projection  186  moves within slot  182  to approximately half-way between the ends of slot  182 . During this movement there is no predefined pivot location because of the somewhat unguided movement of first guide projection (bolt)  70  within first slot  170  between the ends of the slot as leg coupling member  154  translates and rotates relative to foot coupling member  162 . However, when leg coupling member  154  reaches the 10° position shown in FIG.  8 (B), the net result is as if the leg coupling member  154  were thereafter prepared to pivot around an imaginary axis L located well below leg coupling member  154 . 
     However, further translation and rotation of leg coupling member  154  does not result in pivoting around axis L because of the wider end  174  of slot  170 . Instead, from 10° to approximately 35°, first guide projection (bolt)  70  and second guide projection  186  cooperate with their associated slots  170  and  182  to produce a movement as if the outer peripheral surface of leg coupling member  154  “rolled” around the bottom surface of foot coupling member  162  in a camming action. Of course, unlike the first embodiment, foot coupling member  162  does not have a ledge forming such a bottom surface, so this analogy is for illustrative purposes only. In any event, the net effect is a pivoting of leg coupling member  154  around an imaginary pivot point on a pivot axis (Y) that moves horizontally along the bottom edge of foot coupling member  162 . 
     From approximately 35° to approximately 61° leg coupling member  154  pivots around the offset second guide projection  186  and slot  170  rotates so that first guide projection  70  moves from the wider end of slot  170  to the narrower end of slot  170 . The complex compound rotation of leg coupling member  154  in this embodiment more closely approximates the natural movement of the leg inwardly, so this embodiment has particular usefulness in a right side boot, although it could be used in a left side boot depending upon the application. 
     While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the spirit and scope of the present invention. For example, the size, shape, location or orientation of the various components may be changed as desired. The functions of one element may be performed by two, and vice versa. It is not necessary for all advantages or functions to be present in a particular embodiment at the same time. The present invention could be applied to a snowboard boot, an insert for a snowboard boot, a binding, or some other interface between the rider and the snowboard. Various mobility functions may be programmed into the interface by designing different contours of the mating surfaces. Thus, the scope of the invention should not be limited by the specific structures disclosed. Instead, the true scope of the invention should be determined by the following claims.