WO2020008355A1 - Device for carrying boards with improved stability in wind - Google Patents

Abstract

A device for carrying a board on the back of a person improves stability by (a) maintaining a low center of gravity, while keeping all parts of the board from scraping the ground, and (b) using an elastic cinching band to keep the center of gravity of the board close to the person's body, even in the presence of wind forces. Adjustability is improved by an innovative combination of straps which are elastically attached to the board. Wearable comfort is improved by the use of very lightweight materials for the most massive components of the device, which are cushioning pads and a wearable harness.

Description

DEVICE FOR CARRYING BOARDS WITH IMPROVED STABILITY IN WIND

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to and claims priority from commonly owned US Provisional Patent Application Serial Number 62/692,870, entitled "Method and Modular Carrier / Bag for Carrying Surfboards", filed on July 2, 2018, the disclosure of which is incorporated herein by reference in its entirety.

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to equipment carriers, and specifically, to a device for carrying one or more boards, such as surfboards, snowboards, and skateboards.

In many sports and in various kinds of labor, it is necessary for a person to carry one or more large boards. For example, in water surfing, a sportsperson must carry surfboards of about 3.5 meters in length to and from the water's edge. In the field of constmction, a workman is often called upon to carry one or more plywood or plasterboard sheets having lengths of about 8 feet.

The carrying of boards is cumbersome because of their large size and weight, and it presents several specific difficulties. One difficulty is an uneven weight distribution of the load which can lead to muscle stress and fatigue when carrying over long distances. This difficulty has been the subject of numerous papers and patents in the prior art.

However, there are three additional difficulties involved in carrying boards, which have not been adequately addressed by the prior art. The first problem is maintaining stability in the presence of perturbing forces, such as those caused by gusts of wind or changes in ground elevation when climbing a ramp or avoiding an obstacle. The second problem is that the carrying device must be highly adjustable to accommodate a wide variation in people's size and musculature.

The third problem is that, in many applications, the device must be so lightweight and comfortable that it can be worn for extended periods of time, even after the boards have been unloaded. For example, a workman should be able to wear the device comfortably throughout the day, so that it is readily available wherever needed. In the case of a surfboard, it is often the case that surfers enter the water at one location on a beach and exit at another, fairly distant location. In this case, it is desirable that, after using the device to carry the surfboard to the point of entry, the device can be worn comfortably while surfing and then be re-used to carry the surfboard upon leaving the water at the point of exit.

The present invention improves upon existing devices for carrying boards with respect to the abovementioned three problems, namely, stability, adjustability, and wearable comfort.

SUMMARY OF THE INVENTION

The present invention is a device for carrying one or more boards on the back of a person. The device improves stability by (a) maintaining a low center of gravity, while keeping all parts of the board from scraping the ground, and (b) using an elastic cinching band to keep the center of gravity as close to the person's body as possible, even in the presence of strong wind.

Adjustability is improved by an innovative combination of straps which are elastically attached to the boards.

Wearable comfort is improved by the use of very lightweight materials for the most massive components of the device, which are cushioning pads and a wearable harness.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, with reference to the accompanying drawings. The exemplary load in the drawings is a single surfboard, however, it is understood that the principles of the invention apply to one or more boards and to other types of boards of comparable dimensions, such as stand-up paddleboards (SUPs), snowboards, skis, plywood panels, and plasterboard.

In the drawings and specification, references are made to directions such as horizontal, vertical, upright, upper, lower, top, bottom, back, front, and variations thereof. These directional references are exemplary, to show the disclosed subject matter in an example orientation, and are in no way limiting.

Figures 1(a) and 1(b) are back and front perspective drawings of a person wearing the device to carry a surfboard, according to an exemplary embodiment of the invention.

Figures 2(a), 2(b), and 2(c) are perspective drawings of the device according to an exemplary embodiment of the invention.

Figure 3 is a planar view of the device, when all straps are unbuckled, according to an exemplary embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is a lightweight adjustable device for carrying boards. The principles of the present invention may be better understood with reference to the drawings and the accompanying description.

Referring now to the drawings, figures 1(a) and 1(b) show back and front perspective drawings, respectively, of an exemplary embodiment of the invention. Board 10 is carried on the back of standing person 20 with the long axis of the board oriented in an upright position. Upper strap 120, intermediate strap 130, lower strap 140 and U-shaped bottom strap 150 are all adjustable so that they grip board 10 securely. The straps are connected to a wearable harness worn by person 20. The wearable harness, which is shown in figure 1(b), includes two adjustable shoulder straps 170, a front-adjustable belt 180, and a back support 190 (not shown in figures 1(a) and 1(b), but shown clearly in figure 2(b)). Elastic cinching band 160 connects upper strap 120 to the wearable harness, and is made of an elastic material which helps to absorb the shock of wind gusts incident on the upper portion of board 10.

The wearable harness can be adjusted by person 20 while walking, so that board 10 is held firmly against back support 190. This enables person 10 to keep the center of gravity of board 10 as close to his body as possible, which is important for relieving stress and fatigue due to the weight of board 10. The bottom of board 10 is at a height H above the ground, such that it is approximately even with the back of the knees of standing person 20. The value of H is set so that the legs of person 20, when walking, will not bang into the bottom of board 10.

The length of board 10 is denoted by L, and the top of board 10 is at a height equal to (H+L) above the ground. The height of person 20 is denoted by T, and the top of the board 20 extends a distance D=(H+L-T) above the head of person 20, as shown in figure 1(b). The distance D is very important because the top of board 10 is exposed to the wind and may act as a destabilizing "sail" in the worst case, when the wind direction is perpendicular to the board. In that case, the force F applied by wind to the exposed upper portion of board 10 is given by the equation:

F = ( 0.00256 V² ) D W (eqn. 1)

Here, the force F is in units of pounds; the wind velocity V is in miles per hour (mph); D is in feet; and W is the average width in feet of the top of the board over distance D, which roughly corresponds to the so-called "nose width" of board 10.

As a numerical example, suppose board 10 has length L=l0.0 feet and width W=l .8 feet; and person 20 has knee-height H=l .6 feet and height T=5.8 feet. The top of board 10 is then a distance D=(H+L-T)=5.8 feet above the height of person 20. The following table shows F vs. V, as calculated by eqn. 1.

Table 1: Wind Force (F) vs. Velocity (V)

Clearly, the wind force F can be quite large, and, at gusts of V=70 mph (shown in boldface), may even equal or exceed the full body weight of person 20.

Elastic cinching band 160 is specifically designed to absorb the impact of sudden gusts of wind, which might otherwise topple person 20. Elastic cinching band 160 preferably has a length between 8 inches and 24 inches and a cross-sectional area between 0.1 and 0.8 square inches. A good material choice for elastic cinching band 160 is Ethylene Propylene Diene Monomer (EPDM) rubber or Ethylene Propylene Copolymer (EPM) rubber; both of these materials have excellent weather resistance and tensile strengths in the range of 1000 to 3000 pounds per square inch (psi).

Figures 2(a), 2(b), and 2(c) show perspective views of the device according to an exemplary embodiment of the invention. In figure 2(a), adjustable upper strap 120 includes an elastic band 125 to securely hold the upper part of board 10. In figure 2(b), optional front pockets 175 are located on shoulder straps 170, and may be used to hold small items, such as a cellphone and/or keys. Back support 190 is attached, preferably by adhesive and/or stitching, to shoulder straps 170 and to front-adjustable belt 180 so as to form a wearable harness, which is attached to U-shaped bottom strap 150. In figure 2(c), cushioning back pads 195 and cushioning lumbar pad 185 are mounted on the surface of back support 190 which faces board 10.

The material composition of back support 190 is preferably a semi-rigid lightweight polymer material such as high-density polyethylene (HDPE) having a density in the range of 930 to 970 kilograms per cubic meter (kg/m ). Owing to the great strength-to-density ratio of HDPE, an HDPE thickness of 1 to 4 millimeters provides sufficient rigidity for back support 190. An exemplary material for forming cushioning back pads 185 and cushioning lumbar pad 195 is closed-cell, cross-linked Polyethylene Foam having a density of 10 to 60 kg/m³. To protect the foam from abrasion, it is advantageous to cover at least part of the foam with a polymer film, such as nylon or low-density polyethylene (LDPE). The film thickness is preferably in the range of 0.1 to 1 millimeter.

Figure 3 shows a planar view of the device, when all straps are unbuckled, according to an exemplary embodiment of the invention. Upper strap 120 has a male buckle 120M which fits into female buckle 120F. Elastic cinching band 160 has a male buckle 160M which fits into female buckle 160F. Intermediate strap 130 has a male buckle 130M which fits into female buckle 130F. Lower strap 140 has a male buckle 140M which fits into female buckle HOF.

It will be appreciated that the above descriptions are intended only to serve as examples, and that many other embodiments are possible within the scope of the present invention as defined in the appended claims.

Claims

1. A device for carrying at least one board on the back of a person in a substantially upright position, comprising an upper strap elastically attached to an upper portion of said at least one board; an elastic cinching band; and a wearable harness; wherein, said elastic cinching band connects said upper strap to said wearable harness, so as to absorb shocks produced by wind gusts incident on said upper portion of said at least one board.

2. The device of claim 1 further comprising a U-shaped bottom strap elastically attached to a bottom portion of said at least one board.

3. The device of claim 1 further comprising an intermediate strap and/or a lower strap, elastically attached to said at least one board.

4. The device of claim 1 wherein said wearable harness comprises two adjustable shoulder straps, a front-adjustable belt, and a back support.

5. The device of claim 1 wherein said at least one board is selected from a group consisting of surfboards, stand-up paddle boards, snowboards, plywood sheets, and plasterboards.

6. The device of claim 1 wherein said elastic cinching band is comprised of Ethylene Propylene Diene Monomer (EPDM) rubber and/or Ethylene Propylene Copolymer (EPM) rubber.

7. The device of claim 4 comprising at least one cushion which is positioned adjacent to a surface of said back support.

8. The device of claim 4 wherein said back support is comprised of high-density polyethylene (HDPE).

9. The device of claim 7 wherein said at least one cushion comprises Polyethylene Foam.

10. The device of claim 7 wherein said at least one cushion comprises a polymer film.