Snowshoe with adjustable decking tension

The snowshoe having a tubular, elongated, open, main frame, a flexible sheet decking extending over the main frame and defining a peripheral edge section anchored to the main frame, and a telescopic cross-bar, extending transversely of the main frame intermediately thereof. The cross-bar releasably biases the elongated main frame in such a way as to vary its overall width, whereby the widthwise tensioning of the flexible sheet decking is concurrently varied. The sheet decking receives and supports a wearer's foot harness assembly, located directly above the cross-bar.

FIELD OF THE INVENTION 
This invention relates to snowshoes, and particularly to snowshoes having 
adjustable means for facilitating walking over graded or deep snow ground 
terrain. 
BACKGROUND OF THE INVENTION 
U. S. Pat. No. 4,085,529 issued Apr. 25, 1978 to Fred MERRIFIELD, discloses 
a snowshoe having a tubular open frame carrying a fabric decking, 
separated in two spaced apart toe and heel decking sections. The deckings 
are attached to the frame by a plurality of closed loop tie members. A 
fixed length cross-bar member is positioned between the toe and heel 
deckings, and is rigidly affixed transversely to the side portions of the 
frame by collar clamps. The cross-member is adjustable in its fore and aft 
location relative to the main frame, in the gap between the two decking 
portions, thus allowing the wearer to adjust the length of the snowshoe 
forward of the binding location. 
OBJECT OF THE INVENTION 
The main object of the invention is to provide a snowshoe that will have 
means for adjusting the tensioning of the decking in accordance with the 
density of ground snow and with the slope gradient of the ground terrain. 
SUMMARY OF THE INVENTION 
In accordance with the object of the invention, there is disclosed a 
snowshoe comprising: (a) a semi-rigid, open, main frame, defining a main 
inner open area; (b) a flexible sheet decking, extending over said open 
frame main inner open area, and defining a peripheral edge section; (c) 
means for attaching the peripheral edge section of said sheet decking to 
said main frame; and (d) means for adjustably varying the tensioning of 
said flexible sheet decking; whereby said sheet decking is adapted to 
receive and support a wearer's foot. 
Preferably, said tension adjusting means includes an elongated telescopic 
member, extending through said main open area and connected at opposite 
ends to said main frame, wherein said telescopic member adjustably deforms 
the shape of said flexible sheet decking whereby variations in tensioning 
thereof follows. 
The open frame could consist of a tubular member, disposed in an ovoidal 
closed loop fashion; and said adjustment means would then include:--a 
rigid elongated cross-bar member, extending transversely of said main open 
area at an intermediate section of said main frame;--means for mounting 
each end portion of the cross-bar member to transversely opposite sections 
of said frame tubular member; and--telescopic means for varying the length 
of said cross-bar member, The frame tubular member could also include two 
generally U-shape half-sections, and a pair of first and second tubular 
connector members releasably interconnecting the outer ends of each pair 
of coaxially registering legs of said two half-sections of the frame 
tubular member; said mounting means including a radial cavity in said 
first connector member, being fully engaged by a first end portion of said 
cross-bar member, and a radial channel in said second connector member, 
being at least partially engaged by a second end portion of said cross-bar 
member. Preferably, said telescopic means includes the provision of inner 
threads, made into said second connector member radial channel, outer 
threads, made in said second end portion of the cross-bar member, and a 
nut member, threadingly carried by the threaded portion of said cross-bar 
member intermediately of said first and second connector members; whereby 
unscrewing action unto said nut member against the registering tubular 
section of said open frame spreads apart the opposite intermediate tubular 
sections of said open frame and increases the width of said open frame, 
thus tightening the tensioning of said sheet decking. 
The sheet decking may be made from neoprene. 
It is envisioned to add a harness assembly, having a rigid base part and a 
flexible strap part, and hook members pivotally interconnecting said rigid 
base part to said rigid cross-bar member for pitch motion control of the 
wearer, said rigid base part for containing the toe portion of the 
wearer's foot and said strap part for attachment to the wearer's ankle 
portion. A large aperture is preferably made into said sheet decking ahead 
of said harness base part and sized for free partial through-engagement by 
said harness base part and associated wearer's foot, and a rigid gripper 
member, carried transversely of said harness base part, said gripper 
member defining a serrated edge for forcible engagement into frozen ground 
terrain upon forward pitch motion of said harness base part. 
Advantageously, each said tubular connector member includes an intermediate 
diametrally enlarged section, into which the radial cavity and the radial 
channel are respectively lodged, and two opposite tubular segments, each 
tubular segment having an intermediate annular groove, a sealing O-ring 
being lodged into each said groove, each said O-ring frictionally engaging 
with the interior face of the corresponding tubular leg of the open frame 
in fluid-tight fashion. 
Preferably, said peripheral attachment means consists of a number of 
discrete ear loop members, integrally carried at the peripheral edge 
portion of said sheet decking and anchored to the main tubular frame by 
bolt members, successive said ear loop members being spaced from each 
other.

DETAILED DESCRIPTION OF THE DRAWINGS 
As illustrated in FIGS. 1-2, snowshoe 20 includes an elongated peripheral 
tubular frame 22 supporting a flexible sheet decking 24. Open frame 22 
consists of two tubular half-portions 26 and 28, each of generally 
U-shape, with the two frame half-portions 26 and 28 being endwisely 
interconnected by a pair of tubular connector plugs 30, 31 (FIGS. 4 and 
9-10). The two laterally opposite connector plugs 30, 31, are 
interconnected by a cross-bar 32, located intermediately of the rounded 
webs 26a and 28a of U-tubes 26 and 28. Cross-bar 32 includes adjustment 
means 34, detailed later, for adjusting its length, whereby the overall 
width of the snowshoe main frame 22 can be adjustably varied. 
The flexible sheet decking 24 is preferably made from an elastomeric 
material, e.g. neoprene (a trademark), which is made from a lacing of 
nylon strings covered by a layer of rubber. Neoprene is preferred because, 
due to its elastomeric surface, the snowshoe will have a greater traction 
on snow when the wearer engages in graded sloping terrain. 
Decking 24 includes a number of peripheral loop ears 24a, each loop ear 
engaging around a corresponding tubular section 26, 28, of the frame 22 
and being locked in a closed loop condition by locking bolts 25, whereby 
edgewise anchoring of the sheet decking 24 to the frame 22 is achieved. It 
is understood that, as the length-adjustment means 34 of cross-bar 32 is 
actuated, the tightness of flexible sheet decking 24 will also be 
accordingly adjusted. Such tensioning adjustment of the flexible sheet 
decking 24 will be advantageous to adapt to varying snow density 
conditions and graded slope terrain. 
As illustrated in FIGS. 1-8 of the drawings, a foot harness assembly 36 is 
mounted over decking 24 and to the intermediate cross-bar 32, directly 
thereover. Thus, the weight of the wearer will be transmitted through the 
cross-bar 32 to the frame 22, and distributed over the decking. As 
suggested in FIGS. 6-8, the harness assembly 36 will be attached to 
cross-bar 32 by hook members 38 and rotatable around the axis of cross-bar 
32 i.e. will be engageable into pitch movement. Harness assembly 36 
includes an arcuate, rigid, front toe portion 40, an intermediate, rigid, 
shoe portion 42, an intermediate strap portion 43 interconnecting the 
front toe portion 40 and the intermediate shoe portion 42, and a rear, 
flexible, strap portion 44. Straps 43 and 44 attach around the ankle 
portion of the leg of a wearer. 
Intermediate shoe 42 has a generally ovoidal cross-section but is open at 
its top portion, as illustrated, and is integrally connected by its flat 
base wall 42a to the front toe portion 40. Flexible rear straps 44, e.g. 
leather-based, are releasably anchored to the aft end of intermediate shoe 
42, e.g. by a pair of quick-release fasteners 46. 
As illustrated in FIG. 6, a U-shape gripper plate 50 is sandwiched between 
the semi-ovoidal shoe plate 42 and the sheet decking 24. Plates 42 and 50 
are interconnected by a number of nut and bolt assemblies 48, with some of 
the bolts 48 extending through notches 24c made into sheet decking 24 
rearwardly of cross-bar 32. Sheet decking 24 further includes additional 
closed loop ears 24a', being freely mounted by bolts 25' around cross-bar 
32 in register with front sheet aperture 24b and adjacent rear sheet 
notches 24c. The front web of gripper plate 50 forms a transverse flange 
50a having a serrated saw tooth type bottom edge adapted to sink into and 
bite into packed snow and soft ice. 
Each hook member includes a semi-circular channel 38a and an edgewise 
transverse flange 38b. Channel 38a is sized to rotatably fit around 
cylindrical cross bar 32, and extends through respective notches 24c. Bore 
flanges 38b are fixedly mounted by front bolts 48 to gripper plates 50 and 
shoe plate 42. 
Accordingly, as suggested sequentially in FIGS. 7 and 8, the combination of 
shoe element 42, of integral toe element 40, and of gripper element 50, is 
forwardly pivotable with hook elements 38 around pivot shaft 32, from a 
position overlying sheet decking 24 parallel thereto (FIG. 7), to a 
forwardly downwardly tilted position (FIG. 8) in which the shoe and toe 
elements 42 and 40 extend freely through a semicircular front aperture 24b 
of sheet decking 24 (ahead of cross-bar 32) and partially beneath the 
plane of sheet decking 24. Hence, the load of the wearer's foot inside 
shoe element 42 remains always distributed to tubular frame 22 via cross 
bar 32, even during pivotal forward tilt motion thereof around cross-bar 
32. 
Cross bar 32 (FIGS. 4, 5, 6) is cylindrical and includes a first conical 
end portion, 32a, and an opposite threaded end portion 32b. Conical end 
portion 32a engages transversely through an eyelet 33 made into the closed 
loop ear 24a that surrounds connector 30, and into connector member 30, 
through its radial cavity 30a, to come to endwisely abut against the inner 
end seat of cavity 30a at the center of the full connector member 30. 
Opposite end portion 32b engages transversely thorugh an eyelet 33' made 
into the closed loop ear 24a that surrounds connector 31, and a fraction 
of threaded end portion 32b engages threadingly transversely into 
connector member 31, through its radial threaded channel 31a. A nut 52 is 
threadingly carried by the rod threaded end portion 32b exteriorly of 
channel 31a, with nut 52 being located intermediate connectors 30 and 31 
and adapted to press eyelet 33' forcibly against connector 1. 
It can now be understood that, according to the heart of the invention, as 
nut 52 is unscrewed against the inner edge of connector 31, the cross-bar 
32 will be biased to move axially toward the other connector 30, whereby 
the two laterally opposite connectors 30 and 31--and the associated 
respective coaxial legs of U-frame tubes 26, 28--will move away from one 
another, i.e. the main frame 22 will widen. By widening the main frame 22, 
the sheet decking 24 (FIG. 4)--which is loosely anchored to the main frame 
22 by closed loop ears 24a--will progressively tighten. Alternately, by 
screwing nut 52 along threaded cross-bar portion 32b, there is release of 
the bias that widened the frame 22, so that the sheet decking 24 will 
release progressively to resume its unbiased loose condition generally 
illustrated in FIG. 4. 
The screwing adjustment of nut 52 can be easily done manually by the wearer 
himself, simply by bending down and reaching out with his thumb and 
forefinger to the nut 52 beneath decking 24. The wearer need not release 
his snowshoe from his foot, during this operation. 
Each connector member 30, 31, consists of a cylindrical body 54, 54, 
respectively, having an intermediate enlarged section 54a, 54a, through 
which extend the radial cavity 30a or radial channel 31a, respectively. On 
each side of the enlarged cylindrical section 54a, there are provided 
annular outer grooves 54b, 54b, into which are frictionally engaged 
sealing O-rings 56. These O-rings 56 frictionally engage with the 
connector inner face 60a, 60b, bounded by the inner lumen thereof, whereby 
connectors 30, 31, engage therein and interconnect with O-rings 56 in 
fluid-tight fashion. 
The external diameter of cylinder bodies 54--except intermediate enlarged 
section 54a--is sized to fit inside the lumen of the hollow cylindrical 
tubings 26 and 28, while the external diameter of each cylinder body 
intermediate section 54a is sized to correspond to that of tubings 26 and 
28, whereby the two facing ends fo each pair of respective tubing legs 26 
and 28 will come to abut against the annular seats formed about opposite 
ends of intermediate connector section 54a. 
Frame elements 26, 28, and connectors 30 and 31 should be made from a 
semi-rigid waterproof material, e.g. galvanized steel or aluminum, i.e. a 
material being quite rigid yet enabling adjustment of the width of the 
frame 22 by spreading apart the two sides thereof under bias from 
tensioning means 32, 31, 30. The O-rings 56 could be made preferably from 
an elastomeric material. Bolts 25, 48, 48', could be made e.g. from rigid 
nylon.