US3755927A - Snowshoe - Google Patents

Abstract

A plastic snowshoe having a longitudinal blade with an upturned blunt leading edge. The blade is arched from side-to-side with the concave side down to provide a ground-bearing surface. A downwardly extending ''''skeg'''' is positioned within the concavity of the blade to inhibit rearward slippage of the blade while still allowing forward gliding movement. A longitudinal ridge or keel extends along the center underside of the snowshoe blade to improve the structural rigidity of the blade while at the same time preventing ''''ankle roll''''. A conventional binding or foot stirrup is mounted on a horizontal portion of the upper surface of the snowshoe blade. In the preferred embodiment, a removable, friction-fitted transversely extending ''''centerboard'''' is provided to inhibit rearward slippage on extremely steep slopes.

Description

United States Patent [191 Dearborn 51 Sept. 4, 1973 SNOWSHOE {22] Filed: May 25, 1972 [21] Appl. No.: 256,644

[76] Inventor:

Primary Examiner-Patrick D. Lawson Att0meyC. Yardley Chittick et al.

[57] ABSTRACT A plastic snowshoe having a longitudinal blade with an upturned blunt leading edge. The blade is arched from side-to-side with the concave side down to provide a ground-bearing surface. A downwardly extending skeg is positioned within the concavity of the blade to inhibit rearward slippage of the blade while still allowing forward gliding movement. A longitudinal ridge or keel extends along the center underside of the snowshoe blade to improve the structural rigidity of the blade while at the same time preventing ankle roll. A conventional binding or foot stirrup is mounted on a horizontal portion of the upper surface of the snowshoe blade. ln the preferred embodiment, a removable, friction-fitted transversely extending centerboard is provided to inhibit rearward slippage on extremely steep slopes.

10 Claims, 3 Drawing Figures SNOWSHOE BACKGROUND OF THE INVENTION The present invention relates to snowshoes in general and, more particularly, to an improved snowshoe having a downwardly opening, arched, longitudinal, blade with means for inhibiting rearward slippage of the blade while still allowing forward gliding movement of the snowshoe.

Conventinnal, racket-shaped snowshoes provide adequate flotation and traction for the wearer in deep unpacked snow. However, the existing snowshoes offer no possibility for gliding and so must be picked up and out of each footprint and placed just ahead in a deliberate and measured gait. With these constraints, the wearer is limited in his pace through untracked deep snow. By increasing his pace, the wearer invites disaster in the form of catching the leading edge of the snowshoe in the snow.

It is, accordingly, a general object of the present invention to provide an improved snowshoe design.

It is a specific object of the present invention to provide a snowshoe utilizing a pair of lightweight ski-like runners.

It is still another object of the present invention to provide an improved snowshoe which can be readily and inexpensively fabricated from conventional plastic materials.

It is a feature of the present invention that the improved snowshoe design provides the conventional functions of a standard snowshoe in terms of floatation and traction, but which also provides a wearer with additional advantages of forward gliding.

It is still another feature of the present invention that the improved snowshoe includes means for inhibiting rearward slippage of the snowshoe while still allowing forward gliding movement.

It is a further feature of the present invention that the convex upper surface portion of the snowshoe allows the wearer to easily lift the snowshoe out of deep, unpacked snow.

These objects and other objects and features of the present invention will best be understood from a detailed description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which: 21

FIG. 1 is a view in perspective of the improved snowshoe of the present invention showing a portion thereof broken away;

FIG. 2 is a front elevation of the improved snowshoe; and,

FIG. 3 is a view in perspective showing the underside of the improved snowshoe.

Turning now to the drawings, there is shown an improved snowshoe constructed in accordance with the present invention and indicated generally by the reference numeral 10. The snowshoe comprises a longitudinal blade 12 having an upwardly extending leading edge 14, a horizontal portion 16 which provides a mounting surface for a boot binding 18 (shown in FIG. 3) and, in transverse cross-section, a downwardly concave snow-engaging lower surface portion 20 and an upwardly convex upper surface portion 22. Suitable boot mounting holes 24 are provided in the horizontal boot mounting surface 16 to accommodate threaded fasteners (not shown) for securing the boot binding 18 to the blade. It will be appreciated that various mounting systems can be used to secure the conventional boot binding to the blade 12. 6

Although the improved snowshoe 10 can be fabricated from a variety of materials utilizing known fabrication techniques, it has been found that a fiberglass reinforced high density polyethylene is quite desirable. Thus, in the preferred embodiment, the longitudinal blade 12 is formed by injection molding a glass fiber reinforced high density polyethylene. The polyethylene provides the desired surface lubricity for the lower snow-engaging portion 20 and the upper convex surface portion 22.

Given the smooth configuration of the snowshoe 10, it will be appreciated that in deep unpacked snow the wearer can glide forwardly during each step. This is in contrast to existing snowshoes which offer no possibility for gliding. With existing snowshoes, each shoe must be picked up out of each footprint and placed just ahead in a deliberate and measured gait. With such snowshoes, increasing the pace invites disaster in the form of a leading edge caught in the snow. With the im' proved snowshoe 10, the wearers gait more closely resembles that of normal walking. Thus, each foot can be advanced as it is being unweighted, not after it is un weighted. This combined with the gliding ability of the snowshow 10 makes for a pace which is substantially faster than that of conventional snowshoes with a concomitant reduction in physical effort.

ln order to prevent rearward slipping movement of the snowshoe blade inhibiting while at the same time permitting the desired forward gliding movement of the blade, suitable anti-backslip means indicated generally by the reference numeral 26 are provided rearward the showshoe It]. The anti-backslip means 26 can be formed in a variety of ways. For example, a downwardly extending transverse skeg 28 can be integrally molded within the lower concave snow-engaging portion 20 of the blade. The skeg 28, preferably, is flared at its forward end 28a into the forward portion of the blade 12. A removable downwardly extending transverse centerboard M can be inserted in a corresponding well 32 in the snowshoe blade 12. The centerboard 30, preferably, is stepped at 34 to provide a friction-fit within the centerboard well 32. It will be appreciated that the centerboard 30 can be used as an alternative to or in conjunction with the anti-backslip skeg 28. The use of both devices for inhibiting rearward slipping movement of the snowshoe is desirable when snowshoes will be used for climbing relatively steep slopes in unpacked snow. Given the downwardly concave configuration of the lower snow-engaging surface portion 20, it will be appreciated that the loose snow will be compacted within the area and immediately beneath the arch formed by the lower surface portion 20. The compaction and entrapment of the snow densities the snow to provide a better bite for the anti-backslip skeg 28 and/or anti'backslip centerboard 30.

The structural rigidity of the snowshoe blade 12 can be increased, if desired, by means of a longitudinally extending keel 36. In the preferred embodiment, the keel 36 is integrally molded with the snowshoe blade 12. In addition to providing increased structural rigidity, the keel also helps to minimize ankle roll" for the wearer.

Representative dimensions for the improved snowshoe 10 are as follows: length 42 to 50 inches, width 7 5% inches, skeg 28 located approximately 1 foot from the trailing edge 36 of the blade 12, and the head of the boot binding 18 located approximately 26 inches from the trailing edge 36 of the blade. The radius of the downwardly concave snow-engaging lower surface portion is approximately 6 to 8 inches. However, it should be noted that the radius does not have to be constant and in the preferred embodiment, the forward portion of the blade 12 in front of skeg 28 has a flatter radius, e.g., 8 inches, than the portion of the blade behind the skeg 28 which has a radius of approximately 6 inches.

Having described in detail a preferred embodiment of my invention, it will be apparent that a number of modifications can be made therein without departing from the scope of the appended claims. For example, although only one skeg 28 has been shown in the drawings, it will be appreciated that a plurality of skegs can be formed within the downwardly concave snowengaging lower surface portion 20.

What I claim and desire to protect by Letters Patent of the United States is:

1. A snowshoe comprising:

1. a longitudinal blade having an upwardly extending leading edge, a horizontal portion on the upper surface of the blade for mounting a boot binding, and, in transverse cross-section, forward and rearward downwardly concave snow engaging lower surface portions; and,

2. means for inhibiting rearward slipping movement of the snowshoe while allowing forward gliding movement thereof, said means being located between said forward and rearward downwardly concave lower surface portions.

2. The snowshoe of claim 1 wherein said rearward slipping movement inhibiting means comprises at least one transverse, downwardly extending skeg.

3. The snowshoe of claim 2 further characterized by a plurality of transverse downwardly extending skegs.

4. The snowshoe of claim 3 wherein said skeg extends downwardly across the entire width of the rearward downwardly concave lower surface portion.

5. The snowshoe of claim 3 wherein said skeg is flared forwardly and upwardly within said forward concave lower surface portion to provide a smooth transitional surface therein.

6. The snowshoe of claim l further characterized by said blade having at least one longitudinal, downwardly extending keel located within the concave lower surface portions of said blade.

7. The snowshoe of claim 1 wherein said forward and rearward concave downwardly lower surface portions have different radii.

8. The showshoe of claim 7 wherein said forward concave lower surface portion has a longer radius than said rearward concave lower surface portion. 9. The snowshoe of claim 1 wherein said rearward slipping movement inibiting means comprises a removable centerboard means extending downwardly beyond and transversely with respect to the concave downwardly lower surface portions of said snowshoe blade for inhibiting rearward slipping movement.

10. The snowshoe of claim 1 wherein said blade has, in transverse cross-section, an upwardly convex upper surface portion.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3 755 92 DATED September 4, 1973 lN\/ ENTOR(S) Henry Alexander Dearborn It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col.l, line 10, "Conventinnal" should be Conventional--;

Col. 1, line 11, "flotation" should be -floatation-;

Col. 1, line 46, the number 21 should be deleted;

Col. 2, line 30, after "blade" insert --l2- and delete the word "inhibiting";

Col. 2, line 33, after "provided" delete the word "rearward" and insert -in-;

C01. 2, line 42, after "corresponding" insert --"centerboard"- Signed and Sealed this tenth D3) of February 1976 [SEAL] A ttes t:

RUTH C. MA SON C. MARSHALL DANN A lesli g Offizer Commissioner ofPatents and Trademarks

Claims (11)

1. A snowshoe comprising: 1. a longitudinal blade having an upwardly extending leading edge, a horizontal portion on the upper surface of the blade for mounting a boot binding, and, in transverse cross-section, forward and rearward downwardly concave snow engaging lower surface portions; and, 2. means for inhibiting rearward slipping movement of the snowshoe while allowing forward gliding movement thereof, said means being located between said forward and rearward downwardly concave lower surface portions.

2. means for inhibiting rearward slipping movement of the snowshoe while allowing forward gliding movement thereof, said means being located between said forward and rearward downwardly concave lower surface portions.

2. The snowshoe of claim 1 wherein said rearward slipping movement inhibiting means comprises at least one transverse, downwardly extending skeg.

3. The snowshoe of claim 2 further characterized by a plurality of transverse downwardly extending skegs.

4. The snowshoe of claim 3 wherein said skeg extends downwardly across the entire width of the rearward downwardly concave lower surface portion.

5. The snowshoe of claim 3 wherein said skeg is flared forwardly and upwardly within said forward concave lower surface portion to provide a smooth transitional surface therein.

6. The snowshoe of claim 1 further characterized by said blade having at least one longitudinal, downwardly extending keel located within the concave lower surface portions of said blade.

7. The snowshoe of claim 1 wherein said forward and rearward concave downwardly lower surface portions have different radii.

8. The showshoe of claim 7 wherein said forward concave lower surface portion has a longer radius than said rearward concave lower surface portion.

9. The snowshoe of claim 1 wherein said rearward slipping movement inibiting means comprises a removable centerboard means extending downwardly beyond and transversely with respect to the concave downwardly lower surface portions of said snowshoe blade for inhibiting rearward slipping movement.

10. The snowshoe of claim 1 wherein said blade has, in transverse cross-section, an upwardly convex upper surface portion.

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