[0001] The present specification relates to a new type of snowboard binding.
[0002] Snowboarding is a popular winter sport, where a snowboarder rides a board down a
snow-covered slope. The board is attached to the snowboarder by snowboard bindings.
[0003] Broadly speaking, there are two general types of snowboard bindings; step-in bindings,
which requires a boot having dedicated connections which engage with corresponding
connections on the snowboard binding, and strap-in bindings, where the user tightens
straps around the boot to secure the boot to the snowboard. Step-in bindings require
boots adapted to a particular snowboard, which is expensive and inconvenient. Strap-in
boots, though, require the user to bend forward or sit down while securing and tightening
straps around the upper surface of the user's boots behind the toes and in front of
the ankle joint (that is, the instep). The process must be reversed, with the user
leaning forward or sitting down, to release the boots from the bindings.
[0004] Several systems have been proposed to simplify this process, and allow the user to
step into a snowboard binding so that the boot is secured, without having to manually
fasten a strap across the instep. One such system is shown in
US20130147159 (Flow Sports), where the highback is attached to the base plate of the binding by
a cord 117, which is tensioned after the highback is raised using a lever on the back
of the highback.
[0005] Other systems include a bar connected to the highback of the snowboard binding, so
that the highback pivots forward when the user introduces their foot into the snowboard
binding and presses downwards. For example,
US7246811 shows a snowboard binding where the highback and instep strap are closed upon the
user inserted their boot, the instep strap being finally tensioned using a locking
lever. To open the snowboard binding, the user must release the lever. Another snowboard
binding
EP 8249421 shows a mechanism where the highback and instep strap close when the user inserts
a boot into the snowboard binding, the release of the boot being achieved by the user
pulling a lanyard.
WO2009066029 shows a snowboard binding system where cords tensioning the strap of the snowboard
binding are secured by a clamp or cleat, which requires a good quality cleat if the
cord is not to be prone to slippage.
US6003893 shows a snowboard binding where the release is effected by the user operating a lever
or locking unit as an alternative to operating a pull cord, which is inconvenient.
The mechanism also has very little adjustability.
[0006] All these systems require the user to manually operate some component adapted to
allow the snowboard binding to open and release the user's boot, often requiring the
user to sit down or kneel. Particularly in cold conditions, and when wearing gloves
the work required to operate and adjust snowboard bindings can prove cumbersome and
tiring.
[0007] The present invention seeks to address these problems and is designed to work with
standard snowboard boots.
[0008] According to the present invention, there is provided a snowboard binding as defined
by claim 1.
[0009] It will be seen that this allows the user to close the binding while standing up
without any manual operation, and opened, also while standing up, with one simple
movement of the hand, thereby making the process of opening and closing the binding
easier and quicker
[0010] In the following description, the terms forward and rear refer to the front and back
part of the snowboard binding corresponding to the front and back of a user's foot.
The term laterally outward refers to a direction generally horizontal and generally
perpendicular to both the sides of the snowboard binding corresponding to the left
and right side of a user's foot. The terms left and right correspond to the left and
right side of the snowboard binding 10 and foot/boot as viewed in the figures.
[0011] The invention will now be described, by way of example, with reference to the drawings,
of which
Figure 1 is a perspective view of an embodiment of the snowboard binding;
Figure 2 is a side elevation of the snowboard binding in the open position;
Figure 3 is a side elevation of the snowboard binding in the closed position; and
Figure 4 is a side elevation of the snowboard binding showing both the closed (solid)
and open (dotted) positions.
Figure 5 is a side elevation of a detail of the compression plate.
[0012] Referring to figure 1, the proposed snowboard binding 10 comprises a base plate 20,
a highback 30, and strap assembly 35, a tread assembly 40 and a rotation control mechanism
51.
[0013] The base plate 20 is formed with integral vertical side walls 22, 23. The base plate
20 may be attached to a snowboard using conventional 4-screw system, and will typically
include a rotating plate as is known in the art (not here shown).
[0014] The highback 30 is an upright curved structure, and features two lower lugs each
in the form of shaped pulleys 54, 54', which curve forward so that they both lie against
and are pivotally joined to the side walls 22, 23. The highback 30 may be formed in
plastic or carbon fibre, and include cut-out regions to reduce weight as is known
in the art. A highback is often inclined from the vertical, usually leaning forward,
and the precise angle may be adjustable as is known in the art. A strap 69 is attached
to the top of the highback on its outer side. Made of nylon or kevlar, with an additional
grip added at its top, it must be sufficiently rigid and large enough to be easily
grasped by hand, even with gloves or mittens.
[0015] The strap assembly 35 includes a front plate 36 which is shaped to conform to the
instep of a user's boot. The front plate 36 is attached to the rest of the snowboard
binding 10 by two adjustable straps 38, 39 connected to the lower part of the front
plate 36, and by two tension cables 41, 42 attached to either side of the upper part
of the front plate 36. Each tension cable is attached to the front plate with an adjustment
means to adjust the length (and therefore the ultimate tension) of the cable using
adjustment knobs 46, to ensure a comfortable fit. Once the correct length of the tension
cables has been set, the adjustment knobs 46 are locked to withstand the strain caused
during normal use.
[0016] Like the highback 30, the front plate may be fabricated from plastic, carbon fibre
or kevlar.
[0017] The tread assembly 40 includes a compression plate 45 that is configured to lie approximately
parallel with the base plate (that is, approximately horizontal). The compression
plate 45 is approximately rectangular, with the long sides of the rectangle extending
from one side of the binding to the other. The compression plate includes two apertures
(only one of which, 47, is clearly visible) through which the screws of the base plate
20 may be reached. The compression plate 45 is supported by a front rod system 43
and a rear rod system 44.
[0018] The front rod system 43 is a shaped rod having a straight median section which acts
as an axle shaft for the front part of the compression plate 45. This median section
runs in an elongated bore or channel of the compression plate 45 parallel to the compression
plate's edge, and the compression plate is free to pivot around the median section.
Referring also to figure 5 (which is drawn to scale and has some proportions exaggerated),
the section of the channel 49 section is elongated in a direction running from the
front to the back of the compression plate, so that the median section of the front
rod has sufficient play within the channel to slide forwards and backwards along the
compression plate as the compression plate is depressed or elevated when the binding
is going from the opened to the closed position, or vice versa. The median section
is supported at each either end by two parallel, equal length arm sections. These
arm sections each terminate in laterally outward-pointing pivot pins, which each engage
with pivot seats in the side walls 22, 23. The arm sections are perpendicular to the
median section and the pivot pins, so that the pivot pins lie on an axis parallel
to but spaced from the median section.
[0019] The rear rod system 44 is similarly arranged. It too is a shaped rod, having a straight
median section which runs through a channel 52 running the width of the rear part
of the compression plate 45, parallel to the rear edge of the compression plate 45
and allowing the compression plate 45 to pivot about the median section. Two similar
perpendicular arms are angularly disposed from the median section, each arm terminating
in a stub axle that extends laterally. These stub axles are coaxial, and each located
in pivot seats in the side walls 22, 23, and extend through the side walls 22, 23
to engage with the rotation control mechanism 51.
[0020] The rotation control mechanism 51 is located here on the right side of the snowboard
binding 10. It is anticipated that a pair of bindings be made of two symmetrical bindings
so that the rotation control mechanism of each foot faces inwards in the space between
both feet.
[0021] The rotation control mechanism 51 comprises a shaped pulley 54 (best shown in figures
2 to 4), a cammed surface 55, and an enclosed spring 56.
[0022] The shaped pulley 54 and cammed surface 55 are mounted and torsionally secured on
the stub axle of the rear rod system 44, so that the shaped pulley 54 and cammed surface
55 both rotate through whatever angle the stub axle of the rear rod system 44 rotates.
[0023] The left side of the highback also extends to form a shaped pulley 54' which is similar
to that of the shaped pulley 54 on the right side of the highback. The shaped pulleys
54 have an arcuate section 59, and two radial sections 57, 58. The edge of each shaped
pulley 54 has a groove which accommodates the tension cable 41, which runs from the
front plate, over the shaped pulley 54, and terminates behind the pulley, where it
is secured.
[0024] The cammed surface 55 is connected torsionally and coaxially with the shaped pulleys
54, but on the outside of the right side wall 22. The cammed surface is generally
circular in shape, but also includes two flats 61, 62 on its radius. The enclosed
spring 56 is a strong compression spring 64 (the position here being indicated, the
spring itself not being visible), retained in a housing 65. The housing has an open
side, so that the compression spring terminates in a formed head, which can press
against and act on the cammed surface 55 through the open side of the housing 65.
[0025] As mentioned, the cammed surface 55 and shaped pulleys 54, 54' are torsionally secured
to the stub axle of the rear rod system 44. Rotation of the stub axle of the rear
rod system 44 therefore causes the angular rotation of the cammed surface 55 and shaped
pulley 54 about the stub axle.
[0026] Referring to figure 2, the compression plate 45, rear rod system 44 and front rod
system 43 together (together with the side walls 22, 23 on which the rear rod system
44 and front rod system 43 are fixed) form a four bar linkage. When one part of the
system is moved, the other links are thereby constrained to move together.
[0027] The linkage is so configured that when the snowboard binding 10 is in the open position
and the highback 30 is angled backwards, the stub axle of the rear rod system 44 elevates
the compression plate 45 above the base plate 20, the front rod system 43 being constrained
to elevate the front edge of the compression plate 45.
[0028] When the user places a foot into the snowboard binding 10 with a movement indicated
by arrow b, so that the sole of the boot depresses the compression plate 45, the stub
axle of the rear rod system 44 is rotated, causing the highback 30 to rotate by the
same angle as indicated by arrow c, bringing it to a vertical or near vertical position.
The front rod system 43 also rotates, until the compression plate 45 abuts the base
plate 20 of the snowboard binding 10. The rotation of the stub axle (and therefore
the shaped pulley 54 and cammed surface 55) will be approximately 60°.
[0029] Referring now also to figure 3, as the stub axle of the rear rod system 44 rotates,
the shaped pulley 54 also rotates by the same angle. Clockwise rotation (in the sense
shown in figure 2 indicated by arrow
a) of the shaped pulley 54 causes the surface of the arcuate section 59 of the shaped
pulley 54 pull to engage with the tension cables 41. The other end of the tension
cable is drawn in the direction of the shaped pulley 54, which in turn draws the front
plate 36 likewise. Thus, as the sole of the user's boot depresses the compression
plate 45, the front plate 36 simultaneously tightens against the instep of the user's
boot, reaching its maximum tightness when the compression plate 45 abuts the base
plate 20 of the snowboard binding 10.
[0030] The cammed surface 55 of the rotation control mean 51 also rotates as the stub axle
of the rear rod system 44 rotates. While the snowboard binding 10 is in the open position,
the midpoint of the first flat 61 is positioned adjacent to the enclosed spring 56,
so that the free formed head of the compression spring 64 acts against it the cammed
surface 55 at a point where its radius is at a minimum, and the compression spring's
extension is at a maximum. The spring therefore acts against any rotation of the cammed
surface 55 away from this point, and acts to bring the cammed surface 55 back to this
orientation in the absence of a sufficient force to rotate the cammed surface. However,
once the cammed surface 55 has rotated sufficiently for the cammed surface 55 to be
brought into alignment with the second flat 62, the compression spring 64 then acts
to urge the cammed surface 55 to rotate further until the formed head of the compression
spring 64 is acting on the midpoint of the second flat 62.
[0031] The flats shown here are equal in length, so the biasing force towards the open position
and towards the closed position varies symmetrically with angular displacement in
either direction from the overcentre point. If a greater biasing force is desired
to keep the snowboard binding in the closed position (for example), the cammed surface
55 may be varied to effect this. For example, the length of the flat may be increased,
or the shape may be varied to reduce the radius and slope of the cammed surface, such
as excising a scalloped shape from the profile of the cammed surface. The longitudinal
displacement of the spring (and therefore the force it exerts) can be adjusted using
adjustment screw 66. This adjustment must be carried out to take into account the
weight and level of the snowboarder, a higher compression being required for heavier
and/or better snowboarders. The action of the compression spring, particularly after
this adjustment, ensures that the binding does not open accidentally during use.
[0032] The enclosed spring 56 and the cammed surface 55 of the rotation control mechanism
51 therefore acts to bias the ski boot in either the fully open position, or the fully
closed position. Resistance to moving the boot from one position to the other is resisted
until the rotation control mechanism 51 overcentres, after which point the boot is
then urged to the opposition position.
[0033] To secure the snowboard binding 10 then, the user steps into the fully open boot
(with a movement generally by arrow b), depressing the compression plate 45 as previously
described. The force applied by the user's foot overcomes the opposing force of the
enclosed compression spring 56, the rotation control mechanism 51 overcentres and
acts to close the binding securely around the user's boot, with the highback 30 secured
against the user's heel, and the front plate 36 tightly drawn against the user's instep,
securing the snowboard to the user.
[0034] To open the snowboard binding 10 and release the user's boot, the highback is simply
pulled back using strap 69 in the direction generally indicated by arrow e (rotating
around the stub axle of the rear rod system 44) with sufficient force to oppose the
action of the enclosed spring 56, while simultaneously taking weight off the user's
foot, until the rotation control mechanism 51 overcentres, at which point the boot
will spring fully open and the user's boot may be lifted out of the snowboard binding
10 with a movement indicated by arrow d.
[0035] Thus the user can step into the open snowboard binding 10, and the snowboard binding
10 closes and secures the user's feet on the snowboard without having to perform any
manual action, or operate any latch mechanism or fastener on the snowboard binding
10, and therefore the user does not have to lean forward or sit down to attach the
snowboard binding 10.
[0036] Similarly, detachment is a simple process of pulling back on the strap 69 on the
highback 30, without the user having to operate any latch or release mechanism. Since
the strap will usually be situated close to the back of the knee, the user should
be able to open the snowboard binding with a small amount of flexing the knees or
bending, without having to sit or crouch. The opening and stepping out process may
be carried out by the back foot first, allowing the boarder to keep the front foot
attached to the board if needed (e.g. at certain ski lifts), although the front foot
may be removed first if desired.
1. A snowboard binding system having an open position and a closed position for releasably
attaching a boot to a snowboard, the binding comprising:
a base assembly which may include sidewalls
a front assembly, which extends across the area that an upper part or instep of a
boot would present when inserted in the binding in the open position, and applies
a generally downward gripping force in the closed position, the gripping force being
exerted by at least one tension member
a back assembly that pivots about its lower end with respect to the base assembly,
so that it is angled away from a rear surface that a boot would present when inserted
in the binding in the open position, and is angled generally against the rear surface
of a boot in the closed position
a closure control system that synchronises the movement between the open position
and the closed position, including
at least one shaped pulley member that pull or release the tension member
a moveable tread member, that is coupled to the back assembly and the pulley member,
such that when a boot is inserted in the snowboard binding and applies a downward
force to the tread member, the pulley members pull the tension member to move the
front assembly to a closed position, and the back assembly pivots to the closed position
such that when the force on the tread member is removed and a backward pivoting force
is applied to the back assembly, the back assembly pivots to an open position, and
the pulley members release the tension member to move the front assembly to a open
position, and
a biasing assembly, such that the snowboard binding has an overcentre position between
the open position and the closed position
so that when the snowboard binding is between the overcentre position and the open
position the biasing assembly applies a force urging the snowboard binding to the
open position
and when the snowboard binding is between the overcentre position and the closed position
the biasing assembly applies a force urging the snowboard binding to the closed position.
2. A binding according to claim 1 wherein the biasing assembly includes a cammed surface
on which a resilient cam follower acts.
3. A binding according to claim 2 wherein the biasing assembly includes a cammed surface
formed on radial edge of rotatable member.
4. A binding according to claim 2 wherein the biasing assembly includes a rotatable member,
and the rotatable member and pulley members rotate about same axis and are torsionally
coupled.
5. A binding according to any previous claim wherein the tension member is a cable, which
connects the front assembly to the back assembly.
6. A binding according to claim 1 wherein the biasing assembly includes a tread member
coupled to the base assembly by two linkages, which together form a four bar linkage.