CA2249706A1

CA2249706A1 - Downhill snow sport boot assembly

Info

Publication number: CA2249706A1
Application number: CA002249706A
Authority: CA
Inventors: Edward L. Chalmers; William H. Kaufman; Thomas W. Corlett
Original assignee: Individual
Current assignee: William H Kaufman Inc
Priority date: 1996-03-27
Filing date: 1997-03-26
Publication date: 1997-10-02
Also published as: WO1997035494A1; JP2000507136A; EP0891140A1; US5815953A

Abstract

The invention is the assembly of a flexible walking boot (12) and a boot brace (10) made of a rigid material for receiving and holding the boot within it so that the assembly can be used for downhill skiing or snowboarding. The brace has a sole plate (20) for insertion into a conventional downhill ski or snowboard binding. Lateral support is provided by upright members (30, 31) extending along the leg from the sole plate of the brace. Forward resistance is provided by resilient bias means located at the pivotal attachment of the upright members to the brace, which attachment is preferably beneath the heel. The skier's heel is held down by means of an adjustable heel counter positioned at the rear of the brace.

Description

DOWNHILL SNOW SPORT BOOT ASSEMBLY

The invention is a downhill snow sport boot assembly, comprising a boot brace into which a walking boot may be releasably secured. The boot brace may be inserted into a conventional binding for a downhill ski, snowboard or the like, and the assembly provides the user with the control and feel when skiing or snowboarding which is comparable to and in many ways better than that obtained using conventional boots.

The invention is an improvement of prior devices described in United States patents 4959912, 5068984 and 5142798. While these prior devices represented major advances in the art by providing the skier with a viable alternative to the conventional hard shell ski boot, these prior assemblies incorporated means for stabilizing the heel which were not altogether satisfactory, and the resistance to forward lean during skiing was provided by bias means located at the ankle which has also been found to be not wholly satisfactory. The use of a single such bias means on the outside portion of the device tended to produce a twisting torque during use, and the added bulk at the ankle region resulting from the location of the pivot point for the lateral support members of the brace increased the likelihood of interference between the devices during skiing.

The present invention addresses these and other shortcomings of prior embodiments and extends the utility of the invention to related snow sport activities, such as snowboarding. The invention gives the skier all of the essential advantages of a conventional hard shell boot with the further benefit of comfort provided by a flexible, insulated walking boot. While conventional plastic or composite boots require the boot material to provide the skier with medial and lateral stability by virtue of its rigidity, such boots must also allow for some forward flex during skiing, and they must be sufficiently flexible to allow for opening and closing the boot about the foot. Fulfilling these various requirements of support and flexibility necessitates the incorporation of various compromises in the structure, design and performance of a conventional hard shell ski boot. The invention departs from the conventional approach of using a single material to perform various functions by providing a device which separates the mechanical requirements for medial and lateral rigidity and resistance to forward flex from the requirements for flexibility to open and close the boot and to provide a comfortable environment for the foot.

Accordingly, the invention provides a downhill snow sport boot assembly, comprising a flexible walking boot and a boot brace made of a rigid material for receiving and holding the boot within it. The boot brace has a sole plate with toe and heel portions adapted to be insertable into a downhill ski or snowboard binding. A
forefoot receiving means is attached to the toe portion of the sole plate for receiving the toe of the boot.
Inner and outer lateral support members are pivotally attached to and extend upwardly from the heel portion of the sole plate, so that the support members extend laterally along the leg shaft of the boot positioned therein. Resilient bias means are attached to the sole plate at the pivotal attachment of the lateral support members. The resilient bias means provide a gradient of resistance to the forward rotation of the lateral support members. Releasable adjustable instep securement means extend across the boot brace for securing the boot therein, and releasable adjustable leg shaft securement means extend across an upper portion of the lateral support members for securing the leg shaft of the boot.
Heel hold down means at the rear of the brace secure the heel of the boot in.the brace. The heel hold down means comprise a rigid heel counter which is attached to the boot brace, the counter having means for firmly engaging a rear portion of the boot to hold the heel against the sole plate during skiing.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a rear perspective view of a first preferred embodiment of the invention in which the lateral support members are pivotally attached to the sole plate beneath the heel of the boot.

Figure 2 is a front perspective view of the first embodiment.

Figure 3 is a side elevation of a boot and boot brace of the invention as assembled.

Figure 4 is an exploded detail view of a preferred resilient bias means and lateral support member attachment means for the first embodiment.

Figure 5 is a side elevation of the preferred bias means shown in Fig. 4.

Figure 6 is a cross sectional view of the device shown in Fig. 5.

Figure 7 is a rear perspective view of a preferred heel hold down device for use in the invention.

Figure 8 is a side elevation of a boot and boot brace of the invention as assembled showing an alternative heel hold down device.

Figure 9A is a side elevation detail view showing . .

the alternative heel hold down device for the boot brace in the neutral position.

Figure 9B is a detail view of the device of Fig. 9A
showing the heel hold down device in the forward lean position.

Figure 10 is a side elevation of a second embodiment of the invention wherein the bias means is located behind the heel of the boot.

A first preferred embodiment of the improved downhill snow sport boot assembly of the invention is shown in Figs. 1-3. A boot brace 10 provides a structure into which a flexible boot 12 may be releasably inserted.
While the boot 12 is designed to fit the structure of the brace 10, the boot 12 is not of a radically different construction than that of many ordinary winter boots.
Thus, the boot 12 has a toe 13, a heel 14, a leg shaft 15, and a forefoot portion or vamp 16. For use in association with the boot brace 10, the boot 12 has a sole 17 provided with a transverse groove 18 beneath the heel 14 to accommodate structure in the brace 10 described below.

The boot brace 10 has an elongate sole plate 20 which is made of a rigid material, preferable a lightweight moldable thermoplastic or composite material.
The sole plate 20 has toe 21 and heel 22 portions shaped to fit into and to be releasably secured by a standard downhill ski binding. The sole plate 20 may also be formed to fit into and to be releasably secured by a standard snowboard binding.

The brace 10 has a forefoot receiving means 25 for accepting and holding the toe portion 13 of the boot 12.
The forefoot receiving means 25 may simply be a curved W 097/35494 . rCT/CA97100202 --5--toe cap 26 molded integrally with the sole plate 20. The purpose of the forefoot receiving means 25 is to provide a releasable securement of the toe portion 13 of the boot 12 in the brace 10. It will be apparent to the skilled person that this objective may be achieved using various structures.

In a conventional downhill ski boot, the rigid structure of the boot shell provides the skier with the ability to exert control over the ski during use. Thus, such rigid structure enables the skier to have edge control during skiing by providing means for the transverse tilting of the ski in response to the movement of the lower leg of the skier. Without the leverage provided by the rigid boot, the downhill skier does not have the ability to execute quick turns such as those required in the parallel skiing technique. As a result, such a downhill skier would be required to negotiate the slope in a slower fashion for safety, much like a cross country skier. Similarly, a snowboarder exerts control over the snowboard by means of the rigid binding and structural stiffness of the snowboarding boot.

In relation to downhill skiing, the invention provides a rigid structure in the boot brace 10 which allows the skier to exert control over the ski during skiing in the same fashion and with the same feel as is possible using a conventional hard ski boot. Thus, the boot brace 10 of invention has inner and outer lateral support members 30 and 31 which are pivotally attached to and extend upwardly from the heel portion 22 of the sole plate 20. As shown in Figs. 1-3, it is preferred that the lateral support members 30 and 31 extend upwardly and are joined to one another about the rear of the leg shaft 15 of the boot 12 by curved transverse members 33, 34 and 35, but clearly, alternative arrangements of the support members 30 and 31 in relation to the leg shaft 15 are ~-r~ F-'f',~ )/()E~ Wijl~ 41~;:3~ /+~ ).s~ t,.. ~ -po~~ible. Likewise, in this embodiment of the in~ention, the point of pivo~al atC~hment of the ~ateral support ~embers 30 and 31 i~ in the ~ale plate 20 ~eneath the heel of the ~kier. However, a~ will be seen ~ro~ the de~ription of a second e~b~Ai~ent of the invention, the lateral s~pport ~.-~e ~ ~0 and 3 may be attached in alternati~e iooation6 in the heel portion 22 of the sole pla~e 20. m us, the heel portion 22 should ~e understood to include for the purposes of this disclo~u~e the area about the heel of the boot ~race 10, including to the rear a~d generally ben~ath the heel 14 of a boot 12 inserted in the brace lO.

~ t i~ preferred that the support member~ 30 and 31 are form~d a~ a single unit 32 including trans~erse mP~rS, ~uch as the tran6~erse members 33-35. The support mem~r unit 32 ~ay be conveniently molded ~rom a thermoplastic or co~posite material, QUCh a~ a lightweight c~rhon fibre co~po~ite material. The lateral support membors 30 and 31 ~ust h~ve s~fficient ~rength ~nd rigidity to provide the skier with t~e requisite leverage in relation to the ski ~o that the desired edge control during 3kiing ~a~ be readily achieved. In thi~
regard, the ~upp~rt ~embers ~0 and 31 ~u3t be ~haped so ~hat th~y are posltioned sub~tar~tially alon~ the inner and outer lateral portions of the skier'~ lower leg.

~ t i~ pre~ently preferr~d to provide the lateral support me~bers 30 a~d 31 with a lower portion 37 made of matal such as 8tainle6~ ~t~l. In thi~ arrangement, the iateral 6upport unit 32 i6 fon~ed with ~avities at the lower ends o~ the members 3C and 31 ror receivins the metal lower portion6 37, or the u~i~c 32 may simply ~e molded al: out and thoreby secured to the metal lower portions 37. It has be~n ~ound that the combination of a rigid rnetal ~owor portion 37 with a pla~tic or c~mpo~i~e AMENDED SHEET
IPEA/EP

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CA 02249706 l998-09-l6 upper portion 32 provides a number of benefits from a design and functional point of view. Thus, the use of metal and plastic or composite materials allows for the support unit 32 to be either rigid like the metal lower portion 3 7 or to have some degree of give to provide an improved feel to the skier during use.

The lateral support members 30 and 31 are releasably securable about the leg shaft 15 of the boot 12 by means of a strap 38 and closure device such as a buckle 39 to provide adjustability to the securement. The strap 38 is threaded through a shin pad 41 which serves to disperse the forces at the shin of the skier during skiing.
Likewise the support member unit 32 is preferably equipped with a calf pad 42 positioned in front of the upper transverse member 33.

Conventional downhill ski boots provide the skier with the ability to lean into the slope of the hill by allowing a degree of forward flex or give in the boots.
The ability to pivot the lower leg even a few degrees forwardly during skiing provides an essential element of control by enabling the skier to maintain his weight over the skis. The present invention provides this forward lean capability through the use of a resilient bias means 45 attached to the sole plate at the pivotal attachment of the lateral support members 30 and 31, which is preferably through the lower metal portions 37. While the resilient bias means 45 may comprise a variety of structures, the presently preferred means is a torsion spring device such as that shown in Figs. 4-6. Thus, the preferred bias means 45 comprises a torsion spring having and outer tubular member 47, an inner tubular member 48, and an intermediate elastomeric tubular member 49 which is bonded to both the outer and inner members 47 and 48.
Preferably, the elastomer 48 is a rubber material having a thickness of about 1/16 of an inch (1.6 mm). The outer t~iular rnem~er 47 i8 fixed, for example, by molding, inro a plate 51 ~hich in ~urn is mRchanically securable to the sole plate 20 of the Drace 10. The inner tubular ~.e~ber 48 has a plurality o~ flat longit~in~l interior ~urfaces 5~ whi~h in cross 3eCtiOI~ preferable form a regular geometric shape, ~uch a~ a hexagon. A rod 53 h~vi~lg ma_ing longit~l~in~l flat outer ~urface~ i8 in~ertahle into ~he tubul~r member 48, ~o that rotatio~ o~ .he r!~d 53 about its longitudinal axis cau~ec rotation of the inner ~ember 48 relative to t~.e oute_ me~ber 47, whlch r3tation is opposed by the elast~meric ~ember 49.

A preferred assembly for the torsion ~pring 45 ar.d l~teral 6uppo-t ~embers 30 and 31 in thi6 e~b~ nt i~
~hown in Fig. 4. ~he hexagonal rod 53 is sized ~o extend 6_ightly beyond either end of ch~ torsion ~pring 45, and each lower portion 37 ~f the lateral support memb~r6 i6 pro~i~ed with a ~exagonal openi~g sized ~o ~it ov~r ar.
eng~ye an end of the r~d 53. The rod 53 iB tapped w.th an inte~nal ~hread tO receive a cap s-rew 5; at each end to ~ecure each lower lateral support portion 37 ln place.

As will be appa-e~t to the skilied per~on, the foregoing a~se~bly fcr th~ lateral aupport me~bers 30 and 31 to the torsion spring 45 l8 just one o~ ~e~eral poQsible arrangement~ within the scope of the pre~nt in~ention as def ined in the ~Pr~P~ clai~s.

It i~ de~irable to attach the la~eral support member~ 30 and 31, preferably as the unit 32, so that there is a degree ~A praloading of the to~ion soring 45 when the s~port unit 32 i~ secured to the skier's leg.
It has ~een foun~ that a desirable amount of forward ~lex for the skier'~ 'ower leg ~ould be ;imit~d to about 1~~.
Also, the amount ~f resiClance to forward lean which ~he skior feel6 should in-reasc ~teadily and rapidly.
Cl~arly, the tor6ion Bpring 45 can be .ailored to the AMENDED SHEE~
IPEAIEP

various needg of 6kier6, but f or most downhill ~}ciing condition~, the use of a ~pring 45 having a loading force or torgue which proc~ed-~ e~sentially linearly f~om o Lt.
lb~. ~0 joules) at a oD rotati~n o~ the rod 53 relative t~ the fixed outer ~e 47, to 25-3S ft. lbs. (~3.~-47.5 jOU1e~) at 5~, and 80-9Q ft. 1bB~ ~108.5-122 joule~) at 12~, ha~ been found to be suitabLe. The tcrs~i~n spring ~5 -an be readily ~reloaded with a de~ired ~orward re~istance or tor~ y rnanufacturing the spring 45 ~o that the inner tubular ~e,~ . 4~ i~ rotated a deslred am~unt relati~re to the outer tll~v'~r member 49 as gauge~
by the orientation of the geo~netric sha~e o~ ~he inn~r flat surfaces of the inner member 48 relati~e ~o ~he plane 56 of the place Sl (Fig. S). Thi~ off~et or p~eload ar~gle i~or tne tor~ion ~pring 45 relati~re to the neutral position i~ typically in the ran~e of 5-10~, prefera~:Ly about 7~. The a~rerage aTnount of tor~ile preload in this regard is 30-60 ft. lbs. ~4û.7-81.~. joules), but it can be varied as cir~umstar~ce~ require by simply adju~,ing the :nanufacture of the ~pring 45 accordingly. Because ~here is a certain ~mcn~nt o~ f orward give inherent in the boot 12 and shin pad 41, and because the centre~ of rotation are at dif~erent locations, the torsiosl spring 45 nor~slly movee within ~bout a 5' range, whcreaJ the ~ier~3 lower leg may actually pi~rot up co a~ou~ 10 a~out hi 8 ~nklo .

~ rh¢ huT~an leg u~u~lly ha~ some cu~vac~re along it~
le~gth, 80 it i~ desira~le to have an adju~tment mea:rls for the lat~ral 6uppcrt unit 32 to acron~"~o~tc su~h ~urvature. A~ ~how~ in Pig. 4, each lower support portion 37 has a remova~le hexagorlal bushing 57 which in turn ha~ an of~ center hexago!lal opening 58 for receiving the e~d of the rod 53. ~3us~ings 57 on oppcsing l~wer su~port p~rtio~ 3 7 may thu~ be oriented to pro~ride 80me inward or outwar~ tilt to the lat~ral su~l.o~L unit 32 a6 attached to the torsion spring 45, thereby compensating partly or wholly for the leg cu~ature of ~he user.

~MENDED S~EEJ
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-Providing the lateral support unit 32 with the proper degree of tilt assists the skier in maintaining his knee over the ski during skiing. This transverse tilt feature and the application of a torque preload to the torsion spring 45 provides the skier support and stability over the ski when the boot 12 is fastened into the brace 10.

After insertion of the toe 13 of the boot 12 into the toe cap 26, the forefoot 16 of the boot 12 is secured in the brace 10 by a releasable securement means 60. As shown in Figs. 1 and 2, the securement means 60 is preferably a strap 62 and buckle 63 arrangement which includes a forefoot pad 65. The ends of the strap pieces 62 are attached to lateral members 67 extending along both sides of the foot of the boot 12 and behind the heel 14. As shown, the lateral members 67 may conveniently be formed of a single piece of plastic or composite material and attached to the sole plate 20 of the brace 10.

While the leg straps 38 and forefoot straps 62 secure the boot 12 in the brace 10, the skier will still experience some up and down movement of the boot heel 14 during skiing if the brace 10 is not provided with a means for holding the boot heel 14 against the sole plate 20. Since such up and down movement of the boot heel 14 during skiing is quite undesirable, the invention includes a heel hold down means 70 for securing the boot heel 14 against the sole plate 20.

The skilled person will appreciate that there are a variety of devices which may be suitably employed to achieve the objective of holding the boot heel 14 in place during skiing, and a preferred device for use in the present embodiment is shown in Figs. 1-3, and 7.

A first preferred heel hold down means 70 comprises an adjustable heel counter 72 which is positioned behind and preferably above the heel 14 so that upon engagement with the boot 12, it wraps around the heel 14 at a downward angle. The counter 72 should be of a fairly stiff material to provide firm engagement with the heel 14. As shown, the counter 72 is attached to an arm 73 which is part of a pivotally linked pair of arm members 73 and 74. The hinged cojoining of the arms 73 and 74 may be accomplished in a variety of ways, such as by means of a pin 76. The lower end of the arm 74 is pivotally attached by a pin 78 to a receiving structure 79 formed in the lower transverse member 35 of the support unit 32. The upper end of the arm 73 is pivotally attached by a pin 80 to a lever 81 having slots 82 for receiving the pin 80. The lever 81 is in turn pivotally attached to the middle transverse member 34 of the unit 32 by means of a pin 84. This arrangement provides a linkage for allowing the heel counter 72 to move into and away from engagement with a boot 12 positioned in the brace 10.

It is preferable to provide a fine adjustment of the engagement of the counter 72 with the heel 14. One means for accomplishing this objective is by attaching the upper portion of the counter 72 to a screw 90 having a nob 91 which is threaded through the arm 73. Adjustment of the screw 90 using the nob 91 causes the counter 72 to move in and out relative to the heel 14.

It is also important to restrict the rearward movement of the lower pivot arm 74 so that the heel hold down means 70 may provide support at the rear of the boot 12. Thus, it is preferred that a stop 93 be attached to the transverse member 35 to limit the rearward movement of the lower pivot arm 74 when the lever 81 is closed (see Fig. 3).

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CA 02249706 l998-09-l6 A second preferred embodiment of the heel hold down means 70 is shown in Figs. 8 and 9. This embodiment of the invention includes a heel riser 95 affixed to the heel portion 22 of the sole plate 20. A spring loaded resistance means 97 is pivotally attached to an upper portion of the heel riser 95 by means of a pin 98, and the lever 81 is pivotally attached to the support unit 32 by the pin 84.

The resistance means 97 comprises a housing 99 containing a piston 100 having a rod 101 extending through the housing 99 and attached to the arm 73 carrying the heel counter 72. The piston 100 moves in the housing 99 in response to the forward and rearward leg movement of the s~ier. A spring means, such as an elastomer 103, is positioned in the housing 99 to coact with the piston to provide resistance to the forward lean of the skier's leg. Thus, the resistance means 97 supplements the resistance force provided by the bias means 45 located beneath the heel portion 14 of the boot 12.

The inclusion of the spring loaded resistance means 97 in the boot assembly of the invention provides several advantages. The resistance means 97 can function as a fine ad~ustment for the total forward lean resistance of the device 10 provided by the bias means 45 and the resistance means 97. It is more economic to provide an appropriate spring or elastomer 103 to the resistance means 97 for the purpose of increasing or decreasing the resistance force to forward lean, than it is to replace the bias means 45 with one having a different resistance profile. The resistance means 97 can be sized to allow for a greater or lesser degree of forward lean. The limit of travel of the piston 100 defines the limit of forward lean. Thus, both the range and the extent of forward movement of the support unit 32 are governed by CA 02249706 l998-09-l6 W 097135494 . PCT/CA97100202 the structure of the resistance means 97.

The first preferred embodiment of the invention is readily used by simply stepping into the boot brace 10 by first engaging the toe 13 of the boot 12 with the toe cap - 26, followed by seating the torsion spring 45 in the transverse groove 18 of the boot heel 14. The forefoot and leg straps 62 and 38 are fastened, and the heel counter 72 is engaged against the heel portion 14 of the boot 12 by closing the lever 81. With the boot 12 thus secured in the brace 10 and the sole plate 20 of the brace 10 fastened in the binding of the ski or snowboard, the user is ready to commence a downhill run. The device of the invention so assembled will provide the skier with the same feel and control provided by a conventional hard shell ski boot. Using the invention, however, the skier can release the boot 12 from the brace 10 when he is finished skiing and walk normally as the boot 12 is of a flexible construction.

A second preferred embodiment of the invention is shown in Fig. 10. In this embodiment, the resilient bias means 145 is positioned rearwardly of the boot heel 114 in a heel riser 215 attached to the sole plate 120.
Again, the bias means is preferably a torsion spring of the type described. The pivotal attachment of the lateral support unit 132 is also behind the heel 114 at the torsion spring 145. An advantage of this arrangement is that the boot 112 does not need to be specially adapted to fit the brace 110. Locating the torsion spring 145 behind the heel 114 precludes the need to use a boot with a transverse groove in the sole beneath the heel as was the case for the first embodiment described.

The heel hold down means 170 of the second embodiment may simply be a counter 172 attached to a stiffly resilient member, such as a band of spring steel 174, which firmly bia~es the ~ounter into engagement with the rear of the boot 112 ~her, it is ~ecured in the brace 110 .

The remaining f eatures of the secon~ embodiment of the invention are as ~e~cribed previously. The use of this ~ho~ent i~ also ~milar tO that described.

While the ~oregoing de~cription has been direct~d to preferred embo~en~ of the _nvsntion, the skilled per~o~ will apprecia~e that ehe ~cope o~ the invmntion co~er~ a ~ariety of equivalent ~ruecuree. Accordingly, the acope of ~he inventio~ ia int~n~P~ to be covered b~
the following claims.

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Claims

CLAIMS:

1. A downhill snow sport boot assembly, comprising:

a boot (12) made of flexible materials allowing the wearer to walk normally, the boot having sole (17), toe (13), heel (14), and forefoot portions (16), and a leg shaft (15); and a boot brace (10) made of rigid material for receiving and holding the boot (12) within it, the boot brace (10) having a sole plate (20) with toe (21) and heel (22) portions, the sole plate (20) being adapted to be insertable into a downhill ski or snowboard binding, and a boot receiving structure, comprising:
a forefoot receiving means (25) is attached to the toe portion (21) of the sole plate (20) for receiving and holding the toe (13) of the boot (12) in the brace (10);
inner and outer rigid lateral support members (30, 31) are pivotally attached to and extend upwardly from the heel portion (22) of the sole plate (20) so that the support members (30, 31) extend laterally along the leg shaft (15) of the boot (12) positioned in the brace (10);
releasable adjustable forefoot securement means (60) are extendable across the boot brace (10) for securing the forefoot portion (16) of the boot (12) in the brace (10);
releasable adjustable leg shaft securement means (38) are extendable across an upper portion of the lateral support members (30, 31) for securing the leg shaft (15) of the boot (12) in the brace (10);

characterized in that: resilient bias means (45) are attached to the heel portion (22) of the sole plate (20) at the pivotal attachment of the lateral support members (30, 31), said pivotal attachment being beneath the heel portion (14) of the boot (12), the resilient bias means (45) providing a gradient of resistance to the forward rotation of the lateral support members (30, 31) and;
heel hold down means (70) are positioned at the rear of the brace (10) for securing the heel (14) of the boot (12) in the brace (10), the heel hold down means (70) comprising a stiff heel counter (72) which is attached to means for firmly engaging a rear portion of the boot to hold the heel (14) against the sole plate (20) during use.

2. A downhill snow sport boot assembly as claimed in claim 1, wherein the forefoot receiving means (25) is a toe cap (26) convexly curved over and attached to the sole plate (20), the toe cap (26) and sole place (20) defining a space for receiving and holding the toe (13) of the boot (12).

3. A downhill snow sport boot assembly as claimed in claim 1, wherein the inner and outer lateral support members (30, 31) include a transverse member (33, 34, 35) joining them together to form a unit (32).

4. A downhill snow sport boot assembly as claimed in claim 1, wherein the inner and outer lateral support members (30, 31) each include a lower portion (37) which is pivotally attached to the sole plate (20).

5. A downhill snow sport boot assembly as claimed in claim 4, wherein the lateral support members (30, 31) are made of a plastic or composite material and the lower portions (37) are made of metal.

6 . A downhill snow sport boot assembly as claimed in claim 1, wherein the resilient bias means (45) comprises inner and outer parts (48, 47) which co-act with at least one elastomeric member (49) positioned between said inner and outer parts (48, 47) to produce an elastomeric force from the elastomeric member (49) upon rotation of the inner and outer parts (48, 47) relative to one another.

7. A downhill snow sport boot assembly as claimed in claim 6, wherein the resilient bias means (45) is a cylindrical torsion spring having outer and inner tubular members (47, 48) between which an elastomer (49) is bonded to each member.

8. A downhill snow sport boot assembly as claimed in claim 7, wherein the tubular members (47, 48) are metal and the elastomer (49) is a rubber material.

9. A downhill snow sport boot assembly as claimed in claim 7, wherein the inner tubular member (48) has a plurality of flat longitudinal interior surfaces (52), and the torsion spring further comprises a rod (53) being sized to fit within the inner tubular member (48) and having flat longitudinal exterior surfaces which are engagable with the interior surfaces (52) of the inner member (48).

10. A downhill snow sport boot assembly as claimed in claim 9, wherein the rod (53) has ends extending beyond the inner and outer tubular members (48, 47).

11. A downhill snow sport boot assembly as claimed in claim 7, wherein the outer tubular member (47) of the torsion spring is fixed into a plate (51) which is releasably attachable to the sole plate (20) to hold the outer tubular member (47) of the torsion spring stationary .

12. A downhill snow sport boot assembly as claimed in claim 10, wherein the inner and outer lateral support members (30, 31) have openings (58) with internal flat surfaces sized to fit over and engage, the ends of the rod (53) so that the rod (53) may be rotated by the attached lateral support members (30, 31).

13. A downhill snow sport boot assembly as claimed in claim 12, wherein the rod (53) ends are tapped to provide a screw receiving internal thread, and the lateral support members (30, 31) are secured to the rod ends by cap screws (55).

14. A downhill snow sport boot assembly as claimed in claim 1, wherein the boot brace (10) further comprises a pair of lateral members (67) attached to and extending upward from opposing sides of the sole plate (20) and wherein the releasable adjustable instep securement means (60) is attached to the lateral members (67) and comprises a strap (62), buckle (63) and forefoot pad (65) arrangement.

15. A downhill snow sport boot assembly as claimed in claim 3, wherein the lateral support unit (32) comprises a transverse member (33) joining upper ends of the inner and outer support members (30, 31), said transverse member (33) being curved to conform to the shape of a skier's calf, and wherein a calf pad (42) is attached to said transverse member (33 ).

16. A downhill snow sport boot assembly as claimed in claim 15, wherein the releasable adjustable leg shaft securement means comprises a strap (38), buckle (39) and shin pad (41) arrangement attached to the lateral support unit (32).

17. A downhill snow sport boot assembly as claimed in claim 3, wherein the heel hold down means (70) is attached to the lateral support unit (32) .

18. A downhill snow sport boot assembly as claimed in claim 17, wherein the heel hold down means (70) comprises a heel counter (72) which is attached to an arm (73) having upper and lower portions which are hinged together, the lower arm portion (74) being pivotally attached to the lateral support unit (32) and the upper arm portion (73) being pivotally attached to a lever (81) which in turn is pivotally attached to the lateral support unit (32), thereby forming a linkage which causes the heel counter (72) to move into engagement or disengagement with the heel (14) of the boot (12) through manipulation of the lever (81).

19. A downhill snow sport boot assembly as claimed in claim 18, wherein the counter (72) has an upper portion which is attached to a screw (90) having a nob (91), the screw (90) being threaded through the upper arm portion (73), so that rotation of the screw (90) using the nob (91) provides a fine adjustment of the engagement pressure of the counter (72) against the boot (12).

20. A downhill snow sport boot assembly as claimed in claim 3, wherein a heel riser (95) is attached to and extends upwardly from the heel portion (22) of the sole plate (20), and the heel riser is intended to be positioned rearwardly from and adjacent to the boot (12) the heel hold down means (70) comprises a spring loaded resistance means (97) pivotally attached to the heel riser (95) and a heel counter (72) attached to an arm (73) having a lower end attached to the resistance means (97) and an upper end being pivotally attached to a lever arm (81) which in turn in pivotally attached to the lateral support unit (32), whereby the forward movement of the lateral support unit (32) is progressively resisted and the extent of such movement is limited by the spring loaded resistance means (97).

21. A downhill snow sport boot assembly as claimed in claim 20, wherein the counter (72) has an upper portion which is attached to a screw (30) having a nob (91) , the screw (90) being threaded through the arm (73) carrying the counter (72) so that rotation of the screw (90) using the nob (91) provides a fine adjustment of the engagement pressure of the counter (72) against the boot (12).

22. A downhill snow sport boot assembly as claimed in claim 20, wherein the resistance means (97) comprises a housing (99) containing a piston (100) having a rod (101) extending through the housing (93) and attached to the lower end of the arm (73) carrying the heel counter (72);
a spring means (103) is positioned in the housing (99) to coact with the piston (100) to provide resistance to the forward movement of the lateral support unit (32), the housing (99) and rod (101) being sized to define the extent and limit of such forward movement.

23. A downhill snow sport boot assembly as claimed in claim 22, wherein the spring means (103) is an elastomer.

24. A downhill snow sport boot assembly, comprising:
a boot (112) made of flexible materials allowing the wearer to walk normally, the boot having sole, toe, heel (114), and forefoot portions, and a leg shaft; and a boot brace (110) made of rigid material for receiving and holding the boot (112) within it, the boot brace (110) having a sole plate (120) with toe and heel portions, the heel portion having a heel riser (215) attached to and extending upwardly from the heel portion and intended to be positioned rearwardly from and adjacent to the boot (112), the sole plate (120) being adapted to be insertable into a downhill ski or snowboard binding, and a boot receiving structure, comprising:
a forefoot receiving means attached to the toe portion of the sole plate (120) for receiving and holding the toe of the boot (112) in the brace (110);
inner and outer rigid lateral support members pivotally attached to and extending upwardly from the heel riser (215) so that the support members extend laterally along the leg shaft of the boot (112) positioned in the brace (112);
releasable adjustable forefoot securement means extending across the boot brace (110) for securing the forefoot portion of the boot (112) in the brace (110);
releasable adjustable leg shaft securement means extending across an upper portion of the lateral support members for securing the leg shaft of the boot (112) in the brace (110);
characterized in that; resilient bias means (145) attached to the heel riser (215) at the pivotal attachment of the lateral support members, said pivotal attachment being behind the heel portion of the boot (112), the resilient bias means (145) providing a gradient of resistance to the forward rotation of the lateral support members; and heel hold down means (170) at the rear of the brace (110) for securing the heel of the boot (112) in the brace (110), the heel hold down means (170) comprising a stiff heel counter (172) being attached to means (174) for firmly engaging a rear portion of the boot (112) to hold the heel against the sole plate (120) during use.

25. A downhill snow sport boot assembly as claimed in claim 24, wherein the inner and outer lateral support members include a transverse member joining them together to form a unit (132),

26. A downhill snow sport boot assembly as claimed in claim 24, wherein the resilient bias means (145) comprises inner and outer parts which co-act with at least one elastomeric member positioned between said inner and outer parts to produce an elastomeric force from the elastomeric member upon rotation of the inner and outer parts relative to one another.

27. A downhill snow sport boot assembly is claimed in claim 26, wherein the resilient bias means (145) is a cylindrical torsion spring having outer and inner tubular members between which an elastomer is bonded to each member.

28. A downhill snow sport boot assembly as claimed in claim 24, wherein the heel hold down means comprises a heel counter (172) which is attached to a stiffly resilient member (174) which biases the counter (172) into firm engagement with the rear of the boot when the boot (112) is secured in the brace (110).