Abstract:
A snowboard boot includes a heel member and a leg member positioned above the heel member. The heel member and the leg member are secured to the boot so that the leg member is capable of movement relative to the heel member about an axis of rotation that is vertically inclined no more than ±45° and that lies within a plane that is inclined relative to a longitudinal plane which divides left and right sections of the boot.

Description:
BACKGROUND OF THE INVENTION 
     The present invention is directed to snowboard boots and, more particularly, to snowboard boots which bend to accommodate different riding positions. 
     Snowboards differ from skis, which are used in pairs, in that only a single board is used. The rider rides on the snowboard facing sideways so that the direction of snowboard travel and the lengthwise direction of the rider are approximately perpendicular. Both rigidity and flexibility are required of snowboard boots. Rigidity is required so that the foot is held firmly by the snowboard boot, and flexibility is required so that the ankle can tilt with respect to the sole. 
     Some snowboard boots are designed so that the upper and lower regions, particularly the heel section and the cylindrical section or leg section positioned above the heel section, are capable of relative rotation around the approximate centerline of the snowboard boot (the term “approximate” is used because obviously there is not complete lateral symmetry between the left and right boots). Such boots are disclosed in German Patent Publication DE 3,622,746, Japanese Laid-Open Patent Application 7-298092, and elsewhere. In the boots disclosed in these publications, a pivot is used as the swivel design between the heel section and the leg section. The axis of rotation of this pivot lies approximately on the vertical plane which contains the longitudinal line of the snowboard boot. When this type of snowboard boot is used, the ankle can swivel or tilt in unison with the snowboard boot in the lateral direction with respect to the rider. 
     When the snowboard boots are affixed to the snowboard, the left foot is usually positioned to be the controlling foot. The longitudinal line of the left snowboard boot is usually inclined towards the direction of travel (i.e., towards the left side) with respect to the major axis of the snowboard (the direction of forward progress). This angle of incline is usually about 27°. The main reason for this particular angle of incline is that it facilitates vision in the direction of travel. 
     In order to make the snowboard go forward in the direction of its major axis, the tilt or swivel of the left foot should be directed in the direction of travel. In known swivel designs, the direction of tilt is inclined with respect to the direction of travel. That is, in known swivel designs, the direction of tilt is inclined by 27° with respect to the direction of travel. These known swivel and tilt designs result in a loss of the propulsive force which propels the snowboard in the direction of travel. 
     Furthermore, the human ankle is known to have a three-dimensional arch structure that can easily tilt to the left or right when the leg is inclined forward, whereas tilting to the left or right is more difficult when the leg is not inclined. This three-dimensional arch structure thus makes it difficult to bend the foot in the lateral direction when in an erect posture. Swivel and tilt designs must therefore take into account this three-dimensional arch structure, as well as the angle of diagonal attachment of the snowboard boot to the snowboard. Swivel and tilt designs must also be reexamined in connection with piping competition, in which strong propulsive force in the direction of travel is required. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a snowboard boot which allows the rider to apply maximum propulsive force to the snowboard without interfering with the natural movement of the ankle. In one embodiment of the present invention, a snowboard boot includes a heel member and a leg member positioned above the heel member. The heel member and the leg member are secured to the boot so that the leg member is capable of movement relative to the heel member about an axis of rotation that is vertically inclined no more than ±45° and that lies within a plane that is inclined relative to a longitudinal plane which divides left and right sections of the boot. 
     In other words, a snowboard boot which has general lateral symmetry is designed to pivot around an axis which intersects the plane of symmetry. As noted above, tilting motion of the ankle in the lateral direction is facilitated when it is accompanied by tilting motion in the longitudinal direction. Due to the aforementioned three-dimensional structure of the ankle, pivoting motion in a pivoting plane which is inclined with respect to the vertical plane in which the axis of the anklebone lies is easier than pivoting motion in the vertical plane in which the axis of the anklebone lies. Thus, the tilting design which pertains to the present invention is consistent with the three-dimensional arch structure of the ankle. 
     When the snowboard boot is attached such that it is inclined diagonally with respect to the major axis of the snowboard, i.e., to the direction of travel, pivoting motion of the foot in the diagonal direction provides propulsive force in the direction of travel to the snowboard boot. Since the rotational force (the component force which acts so as to rotate the snowboard) is zero or very small in this case, the loss in propulsive force produced by the foot acting on the snowboard is minimized, and this propulsive force therefore has high propulsive efficiency. This high propulsive efficiency is useful in piping competitions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an inclined projection of a particular embodiment of an insert for a snowboard boot according to the present invention; 
     FIG. 2 is a top cross sectional view of the insert shown in FIG. 1; 
     FIG. 3 is a cross sectional view of the insert taken along line III—III of FIG. 2; 
     FIG. 4 is an inclined projection of an alternative embodiment of an insert for a snowboard boot according to the present invention; 
     FIG. 5 is a top cross sectional view of the inset shown in FIG. 4; 
     FIG. 6 is a cross sectional view of the insert taken along line VI—VI in FIG. 5; 
     FIG. 7 is a top view of another alternative embodiment of an insert for a snowboard boot according to the present invention; 
     FIG. 8 is a left side cross sectional view of the insert shown in FIG. 7; 
     FIG. 9 is a plan view of the insert shown in FIG. 7; 
     FIG. 10 is a top view depicting the positional relationship of a pair of snowboard boots attached to a snowboard; 
     FIG. 11 is an inclined projection depicting bending motion of the foot for both feet; 
     FIG. 12 is an inclined projection depicting bending motion of the foot for the left foot; 
     FIG. 13 is a partial cross sectional view of a particular embodiment of a snowboard boot which incorporates a hinged member according to the present invention; and 
     FIG. 14 is a side view of an alternative embodiment of a snowboard boot which incorporates a hinged member according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     A first embodiment of the snowboard boot according to the present invention will now be described. Ordinary snowboard boots have a rigid sole, a rigid heel section, and a rigid toe section. This rigid sole material is covered by a soft insole member and by other facing materials. In order to reinforce the heel, a rigid member (termed a heel cup, etc.) is attached on the inside or the outside of the facing material. The rigid heel cup is affixed to the sole or facing material in the heel section by stitching or bonding. The rigid heel cup consists of a rigid material such as nylon 66. A leg section extends generally vertically upward from the heel section, and this leg section may include a rigid member to stiffen all or a portion of the leg section. 
     FIG. 1 depicts a particular embodiment of a rigid heel cup  1  and a leg section rigid member  11  which may be used in a snowboard boot according to the present invention. Heel cup  1  comprises a heel cup attached at the inside of the shell of the snowboard boot. The rigid heel cup  1  is a heel cup consisting of a heel section  2 . The inside and outside surfaces of the heel section  2  are bowed such that the outside has convex curvature. The rigid heel cup  1  extends out to form a continuous bottom section  3  (FIG. 2) that is bonded to the sole (not shown). The right and left shoes are usually positioned in mirror symmetry to each other, but the left and right shoes are not themselves symmetrical. In this embodiment, the heel section  2  in each shoe is laterally symmetrical. That is, when the shoe is placed on a horizontal plane, the heel section is approximately symmetrical with respect to a vertical longitudinal plane which contains a line in the longitudinal direction. This approximately symmetrical plane is referred to herein as the “plane of approximate symmetry.” 
     In FIG. 1, the right side of the plane of approximate symmetry S is the outside and the left side of the plane of approximate symmetry S is the inside. Thus, the rigid heel cup  1  depicted in the drawing is for the right foot. In this embodiment, the top edge at the back of the heel section  2  has a curved shape that is symmetrical with respect to the plane of approximate symmetry S. This curve comprises an outside upward-protruding convex line segment  4  forming an outside protrusion  6 , an inside upward-protruding convex line segment  5  forming an inside protrusion  7 , and a central concave line segment  10  that is projected concavely downward at the center. 
     A leg section rigid member  11 , contained in the leg section of the snowboard boot, is located above the rigid heel member  1 . The rigid material used for the leg section rigid member  11  is softer than that used for the rigid heel member  1 . The leg section rigid member  11  is a member that provides support to the back of the ankle. The lower edge at the bottom of the leg section rigid member  11  has a curved shape that is symmetrical with respect to the plane of approximate symmetry S. This curve comprises an outside downward-protruding convex line segment  12  forming an outside protrusion  14 , an inside downward-protruding convex line segment  13  forming an inside protrusion  15 , and a central convex line segment  20  that is projected convexly upward at the center. The outside protrusion  6  and the outside protrusion  14  overlap in the longitudinal direction, and the inside protrusion  7  and the inside protrusion  15  overlap in the longitudinal direction. In this embodiment, the outside protrusion  6  and the inside protrusion  7  are assumed to be positioned in front of the outside protrusion  14  and the inside protrusion  15 , but this placement is not critical and is a matter of design choice. 
     The outside protrusion  6  and the outside protrusion  14  are offset to the right with respect to the plane of approximate symmetry S, and the inside protrusion  7  and the inside protrusion  15  are offset to the left. The axis of rotation L is defined as the straight line which passes through the center point O (the position which is the approximate center position of the outside protrusion  6  and the outside protrusion  14 ) and which intersects the plane of approximate symmetry S. The axis of rotation L has a downward slope in the forward direction, so the axis of rotation L also intersects the plane of the sole. Whether the axis of rotation L has a downward slope or an upward slope in the forward direction is a matter of design. However, a downward slope is favorable in terms of providing a secure fit in the snowboard boot when the foot is inclined forward. The area in which the axis of rotation L intersects the rigid heel cup  1  and the leg section rigid member  11  takes the form of a hinge. 
     FIG. 2 depicts the overlapping structure of the outside protrusion  6  and the outside protrusion  14 . The outside protrusion  6  is rotatably fixed to the outside protrusion  14  by means of a position-fixing rivet  17 . The position-fixing rivet  17  is provided with a pivot or rotating shaft  18 , wherein the axis of the rotating shaft  18  is aligned with the axis of rotation L. The face at which the overlapping outside protrusion  6  and the outside protrusion  14  slide together is a spherical face or approximately spherical face  19 . The clamping force exerted in the axial direction by the position-fixing rivet  17  is designed to be low in order to minimize frictional force at the spherical face between the outside protrusion  6  and the outside protrusion  14 . 
     FIG. 2 also depicts the overlapping structure of the inside protrusion  7  and the inside protrusion  15 . In this embodiment, the position at which the inside protrusion  7  and the inside protrusion  15  overlap is located symmetrically to the position at which the outside protrusion  6  and the outside protrusion  14  overlap with respect to the plane of approximate symmetry S. The overlap face  22  at which the inside protrusion  7  and the inside protrusion overlap has the shape of an arc or a group of arc-shaped curves. In FIG. 2, the radius of the arc is indicated by R. 
     FIG. 3 is a cross section cut along the vertical plane which contains the orthogonal line  24  indicated in FIG.  2 . The point of intersection of this vertical plane and the axis of rotation L is indicated by P. As shown in FIG. 3, the cross section of the overlap face between inside protrusion  7  and inside protrusion  15  has an arc or an arc-like shape. The line of the arc or arc-like shape will henceforth be termed “approximate arc  23 ”, and it has point P as its center. The inside protrusion  7  is a part of the rigid heel cup  1 , and it has a thick section  26 . The outside surface of the thick section  26  and the inside surface of the inside protrusion  15  together form approximate arc  23 . 
     In FIG. 2, the direction of snowboard travel is indicated by the arrow  31 . The case of propulsive force being exerted on the snowboard towards the right side in FIG. 2 will be described. When the right ankle is bent downward in the direction of the sole or of snowboard travel (towards the upper left of the drawing), the rigid leg section member  11 , whose curvature conforms to the back of the ankle, attempts to bend down together with the ankle towards the inside (towards the left leg). When the rigid leg section member  11  is subjected to this pivoting force or thrust, it tilts and rotates in the counterclockwise direction with the free rotation center point (point O) as the center of rotation. The inside protrusion  7  and the inside protrusion  15  are in contact via the arc  23  and slide smoothly. 
     This tilting occurs on a plane which intersects the plane of approximate symmetry S of the snowboard boot, so resistance is produced by the snowboard boot which has an approximately symmetrical design with respect to the plane of approximate symmetry S. This resistance, which is produced by the structure comprising the rigid heel cup  1  and the leg section rigid member  11  that are in contact through a curved face, restricts the pivoting force against the rigid heel cup  1  and the leg section rigid member  11  so that excessive pivoting is prevented. This resistance, which does not depend upon sliding frictional force between the outside protrusion  6  and the outside protrusion  14  or sliding frictional force between the inside protrusion  7  and the inside protrusion  15 , is determined by the three-dimensional arch structure of the snowboard boot, and is thus always held stable at an essentially constant level. The concave section formed between the outside protrusion  6  and the inside protrusion  7  allows the rigid heel cup  1  to deform smoothly, and the concave section formed between the outside protrusion  14  and the inside protrusion  15  allows the leg section rigid member  11  to deform smoothly. The propulsive force of the snowboard will be discussed in greater detail later. 
     FIGS. 4,  5 , and  6  depict an alternative embodiment of a snowboard boot according to the present invention. FIGS. 4,  5 , and  6  are identical to FIGS. 1,  2 , and  3 , except with regard to the points noted below. In the first embodiment, no means is provided for coupling the inside protrusion  7  and the inside protrusion  15  in the longitudinal direction. This embodiment differs from the first embodiment in that means is provided for coupling the inside protrusion  7  and the inside protrusion  15 . 
     As shown in FIG. 4, the inside protrusion  15  is perforated by a slot  41 , and the inside protrusion  7  is perforated by a round hole  42 . A rivet  43  is passed through the slot  41  and the round hole  42 . Both ends of the rivet  43  are flattened so that the inside protrusion  7  and the inside protrusion  15  are loosely coupled in the longitudinal direction. The slot  41  takes the form of a single arc having the axis of rotation L as its center, and the angle over which the slot  41  extends from its top edge to its bottom edge with reference to the axis of rotation L (at reference point θ) is designated θ. The shaft of the rivet  43  is located in the vertical plane that contains the orthogonal line  24  and on the line that passes through point P. When the leg section rigid member  11  pivots relative to the rigid heel section  1 , the rivet  43  moves approximately vertically within the slot  41 . 
     FIGS. 7,  8 , and  9  show another alternative embodiment of the present invention wherein metal is substituted for resin as the material for the insert. FIG. 7 shows a metal heel member  51  that constitutes the rigid heel cup. FIG.  8  and FIG. 9 show the metal heel member  51  of the rigid heel cup and a leg section metal member  56  of the leg section rigid member in the assembled state. In this embodiment, the metal member  56  is positioned behind the metal member  51 , but the longitudinal relationship of the two elements is a matter of design. Metal members  51  and  56  are for use on the right foot. 
     Metal member  51  comprises a heel section  52  and a curved member  53  of band form. The heel section  52  rises at a backward incline from the central section of the curved member  53 . A spherical surface  54  (FIG. 7) is formed on the outside (the rear surface) of the heel section  52 , and a pivot hole  55  perforates the heel section  52 . The metal member  56  is positioned above the heel section  52 , and it is coupled rotatably to the heel section  52  by a rotating shaft (not shown). The section of the metal member  56  that contacts the heel section  52  has a spherical surface that matches the spherical surface  54 . 
     In FIG. 7, the direction of snowboard travel is indicated by arrow A. The axis of rotation L of the metal member  56  is approximately orthogonal to the direction of travel and slopes slightly downward. That is, the axis of rotation L intersects the plane which contains the plane of the sole. The metal member  51  is perforated in several places by bolt holes  57  so that the metal member  51  may be fixed securely to an elastic shell  59  of a heel section of the snowboard boot by bolts (not shown) which pass through the bolt holes  57 . The metal member  56  is also provided with a plurality of bolt holes  58  which are lined up in the vertical direction. The metal member  56  may fixed securely to an elastic shell  60  of a leg section of the snowboard boot by bolts (not shown) which pass through the bolt holes  58 . 
     When the boots are fixed to the snowboard, the plane of approximate symmetry of each snowboard boot can be defined as follows. When the insides of both feet are placed together so as to touch lightly at two points while standing erect, the plane of approximate symmetry is the vertical plane that is parallel to the plane containing these two points, and that contains the back end point of the heel section, which has an approximately spherical surface shape. A right side plane of approximate symmetry SL and a left side plane of approximate symmetry SR defined according to these terms for the left and right foot are depicted in FIG.  10 . 
     In FIG. 10, the direction that is usually designated as the direction of travel is indicated by arrow B. That is, the snowboard is propelled towards the left foot, which is generally the controlling foot. The major axis of the snowboard  61  is indicted by the number  62 . The major axis  62  is parallel to the direction of travel B during straight forward advance. The left foot is the controlling foot, and, compared to the left foot, the right foot contributes almost nothing to propulsive force. 
     The snowboard is propelled in a way that at first appears to contradict the third law of motion. Where the right foot and the left foot exert equal force on the snowboard, the snowboard is not propelled forward since the snowboard and the rider are in an internal force relationship. To state the case in exaggerated terms, the pivoting/tilting structure for the right foot is not very important when the snowboard is propelled unidirectionally to the left. 
     In this embodiment, the plane of approximate symmetry SL is inclined counterclockwise by 27° with respect to the orthogonal line  63  that is orthogonal to the longitudinal direction, i.e., the major axis  62  of the snowboard. The plane of approximate symmetry SL is inclined in such a way that the front of the foot is pointed more in the direction of travel than is the back of the foot This 27° angle is an optimum value arrived at on the basis of a rule of thumb. Of course, the optimum angle will differ depending on the degree of skill, the type of competition, and the individual characteristics of each rider. The pivoted section, which is the origin of the pivot position of the axis of rotation LL on the left side (the hinge member which is the intersection at which the axis of rotation LL intersects the heel section and the leg section), is offset clockwise from the plane of approximate symmetry SL. The angle between the axis of rotation LL and the plane of approximate symmetry SL is set at 30°. Thus, the axis of rotation LL is contained in an inclined plane which inclines inward at the front. 
     Usually, the angle formed between the plane of approximate symmetry SL and the inclined plane  64  (the vertical plane which contains the axis of rotation LL) is within the range of 23° to 33° for the foot that is located forward in the direction of travel. The angle formed between the plane of approximate symmetry and the orthogonal line  63  is within the range of 20° to 30° for the left foot. In this embodiment, the angle formed between the plane of approximate symmetry SL and the corresponding inclined plane LL is not smaller than the angle formed by the plane of approximate symmetry SL and the orthogonal line  63 . For example, 30° versus 27°, as noted above. Under these conditions, the axis of rotation LL is approximately parallel to the orthogonal line  63 . In the illustrated embodiments, the angle formed between the axis of rotation LL and the orthogonal line  63  is set to 3°, so these two are approximately parallel. 
     In this embodiment, the plane of approximate symmetry SR is inclined by 6° counterclockwise from the orthogonal line  63  which is orthogonal to the longitudinal direction, i.e., the major axis  62  of the snowboard. Thus, the plane of approximate symmetry SR is inclined in such a way that the front of the foot is pointed more in the direction of travel than is the back of the foot. This 6° angle is an optimum value arrived at on the basis of a rule of thumb. Therefore, the optimum angle will differ depending on the degree of skill, the type of competition, and the individual characteristics of each rider. 
     The pivoted section, which is the origin of the pivot position of the axis of rotation LR on the right side, is inclined clockwise from the plane of approximate symmetry SRF The angle between the axis of rotation LR and the plane of approximate symmetry SR is set at 5°. Usually, the angle formed between the plane of approximate symmetry SR and the inclined plane  65  (the vertical plane which contains the axis of rotation LR) is within the range of 0° to 8° for the foot that is located to the rear in the direction of travel. The angle formed by the plane of approximate symmetry SR and the orthogonal line  63  is within the range of 0° to 10° for the right foot. 
     In this embodiment, the angle formed between the plane of approximate symmetry SR and the inclined plane  65  is not greater than the angle formed by the plane of approximate symmetry SR and the orthogonal line  63 . For example, 5° versus 6°, as noted above. Under these conditions, the axis of rotation LR is approximately parallel to the orthogonal line  63 . In the illustrated embodiments, the angle formed by the axis of rotation LR and the orthogonal line  63  is set to 1°, so these two are approximately parallel. The axis of rotation LL and the axis of rotation LR intersect, in which case, the angle formed by the two axes is 4°. 
     By shifting the body weight forward and moving the center of gravity of the body forward, the left foot (which is the controlling foot) becomes the principal point of action, and the snowboard is propelled forward, as depicted in FIG.  11 . In this case, the left foot is inclined more towards the front than is the right foot, as depicted in FIG.  12 . It is difficult to incline the foot to the left without inclining it forward. 
     Because of its three-dimensional arch structure, the foot does not readily rotate with the plane of approximate symmetry SL as the axis of rotation. Rather, the foot usually twists while inclining forward and rotates in a plane that is inclined with respect to the plane orthogonal to the plane of approximate symmetry SL. The angle of inclination is about 30° at the greatest the step-in location. To accommodate this fact, in a snowboard boot according to the present invention the rotation mechanism of the leg section rigid member  11  is designed to faithfully reflect this rotation mechanism of the foot. In other words, for the left foot the leg section rigid member  11  is positioned to rotate around the axis of rotation LL in the inclined plane  64  that is inclined about 30° with respect to the plane of approximate symmetry SL. Thus, the foot can pivot together with the snowboard boot without undue strain. Furthermore, the direction in which the foot pivots is approximately in the vertical plane which contains the major axis  62  of the snowboard. The shift in the center of gravity produced by pivoting of the foot effectively generates propulsive force in the direction of travel of the snowboard (direction B). With conventional pivot mechanisms, the force F applied to the snowboard by the foot produces a lesser thrust of cos(30)·F and requires a bending motion which is at odds with the structure of the foot. 
     FIG. 12 illustrates the difference between motion of a conventional snowboard boot and a snowboard boot according to the present invention. As illustrated in FIG. 12, as an arbitrary point P located on a forward-leaning leg rotates around an axis  101  which extends in the longitudinal direction of the foot (as in a conventional pivoting snowboard boot), the location of the point defined by dropping down from point P at a right angle to the horizontal plane shifts from Q 1  to Q 2 . The straight line which connects Q 1  and Q 2  is parallel to the line  102  which is orthogonal to the axis  101 . From the standpoint of the three-dimensional arch structure of the foot, such rotation is difficult. 
     When the foot rotates by an angle γ (not shown) on an axis defined by an inclined line  104  inclined inward from the axis  101  by a certain angle (30° in the embodiment described), point P shifts from Q 1  to Q 3 . The straight line which connects Q 1  and Q 3  is parallel to the line  105  which is orthogonal to the inclined line  104  which is the axis in this case. From the standpoint of the three-dimensional arch structure of the foot, such rotation is easy. The fact that, under circumstances of a reasonable degree of rotation, the relationship between the angle of lateral rotation γ and the longitudinal angle θ is such that γ=F(θ) can be readily ascertained by bending the leg. This type of motion is used in snowboarding. 
     In piping competition, the direction of travel is both to the right and to the left. In this case, the plane of approximate symmetry is designed to be approximately orthogonal to the direction of the major axis of the snowboard. The inclined planes  64  and  65  are inclined at angle of less than 30° with respect to the plane of approximate symmetry. This has the advantage that even if a loss that reduces the component force in the direction of travel should be produced, the extent of the loss is less than that which would occur had bending of the foot not been facilitated. 
     FIG. 13 is a partial cross sectional view of a particular embodiment of a complete snowboard boot  150  according to the present invention. In this embodiment, the snowboard boot includes outer leather layer  154 , a middle foam layer  158 , and an inner liner layer  162 . This type of multi-layer cylindrical structure serves as a rigid reinforcing structure for the snowboard boot. A pivoting structure similar to the structure shown in FIGS. 7-9 is provided in the middle layer of the boot. This pivoting structure comprises a heel cup  166 , a metal heel member  170  fixed to heel cup  166 , a metal leg member  174  rotatably coupled to metal heel member  170 , and a rigid leg member  178  fixed to metal leg member  174 . A flexible soft and expandable section  182  is provided between the upper and lower portions of the boot at the approximate location of pivoting of the hinge formed by metal heel member  170  and metal leg member  174 . Section  182  may include a flexible rubber layer  186  covering the hinged section. With this snowboard boot, the pivoting structure is completely embedded and protected within the boot. 
     FIG. 14 is a side view of an alternative embodiment of a snowboard boot which incorporates a hinged member according to the present invention. In this embodiment, the hinged member is disposed on the outside of the boot. In this case, rigid member  178  may be optionally provided inside the boot, or else it could be provided on the outside of the boot. 
     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 snowboard boot according to the present invention can be used with a step-in type snowboard. In this case cleats are attached to the snowboard boot, and the snowboard may be provided with a disk-type engagement mechanism in which the cleats are engaged by a step-in system. The disk to which the snowboard boot is attached is stationary at the desired rotation position, wherein the axis of rotation rotates in tandem with the snowboard boot so that the angular relationship of the snowboard boot and the snowboard may be changed. The hinge member of the snowboard boot can be designed so as to be moveable. Continuous motion of the hinge member is not required. Insertion holes or the like can be provided in several locations for attaching the hinge member. When moving the position of the hinge member, the angle of incline of the axis of rotation may be changed as well. 
     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. Of course, although labeling symbols are used in the claims in order to facilitate reference to the figures, the present invention is not intended to be limited to the constructions in the appended figures by such labeling.