Tent – canopy – umbrella – or cane – Portable shelter – Framework
Reexamination Certificate
2001-06-28
2003-01-07
Horton, Yvonne M. (Department: 3635)
Tent, canopy, umbrella, or cane
Portable shelter
Framework
C135S128000, C135S143000, C160S135000, C160S370210, C160SDIG002, C446S478000, C446S488000
Reexamination Certificate
active
06502596
ABSTRACT:
This invention relates generally to freestanding structures such as tents and the like.
BACKGROUND AND SUMMARY OF THE INVENTION
For thousands of years, large-scale tensioned fabric structures have been used as shelter and protection for groups of people. Large-scale structures pre-date the smaller versions, typically used by two or three people, which were designed only in the last few centuries. Innovations and improvements have modernized virtually every aspect of the smaller versions and currently the field of invention for these structures is very crowded and a minor advance carries great weight. Despite the overcrowding of patentable art in the field of small structures, most of these improvements have not been practiced on larger-scale structures, leaving these designs crude in comparison. It has been more than 30 years since large-scale design having today's widest commercial and industrial acceptance was developed.
All present-use tensioned fabric structures utilize some sort of weight-bearing pole framework which forms a skeleton upon which the fabric cover is suspended. As such, the pole framework performs the function of supporting the fabric weight and the fabric cover performs the separate function of establishing the structure's sheltering walls and roof. In prior-art structures, the two functions work against each other to create the tension referred to in the generic Class of this invention, “Tensioned fabric structures”. In the author's opinion, all prior-art design wrongly separates these two functions into opposing roles. By not integrating the support and covering functions in a cooperative, co-active role, present-use structures suffer from a number of disadvantages. My prior U.S. Pat. No. 5,343,887 describes the disadvantages suffered in the field of small-scale structures; this present invention addresses the various types of problems suffered by large-scale structures.
One of the principal problems with large-scale structures is that associated with erecting them. The assembly process is complicated and exacting, rendering set-up by one person impossible and often three or more persons are required. The process involves unpacking a bewildering assortment of pole segments, stakes, guy-lines and an enormous flaccid fabric cover which is many times bigger than, and has no apparent relationship to, the structure's final set-up shape. The most rudimentary embodiments require a minimum of six vertical rods (each of which is typically longer than five feet), at least three horizontal support poles (each usually has a length of more than seven feet), and several (the simplest structure requires eight) stakes and/or guy-lines. The set-up and trimming process guarantees that the assembly procedure of all prior-art large-scale structures is never the same twice, each is a laborious and custom installation. If the users suffer from lack of experience or a momentary negligence, they may upset the delicate balance of the partially-erected structure at any time during the set-up procedure, causing them to start again and all their progress lost. Furthermore, if any one of the components is lost, torn, broken or misplaced, set-up of these prior-art structures could be impossible.
Present-use large-scale design requires users to anchor the fabric cover to the terrain with stakes, guy-lines or the like. This is a second handicap as such structures are incapable of being relocated after they are assembled. The tensioned support is violated when any stake, rod or other anchoring mechanism is moved; relocating involves dismantling the frame and extensive anchoring means and rebuilding from the beginning. Structures lacking freestanding capability are also unsuitable for scree, rocky or sandy terrain.
The weight of prior-art large-scale structures is a third liability which smaller-structure design has attacked zealously. It is not uncommon for a smaller structure accommodating two users to weigh as little as three or four pounds while larger structures accommodating six users can weigh more than sixty pounds. The inefficient distribution of stresses in large-scale prior-art design, caused by separating the support function from the covering function as described previously, feeds a vicious circle of ever-increasing weight: heavier framing members require heavier fabrics which in turn require enhanced frame support, calling for still heavier fabrics, etc., etc., etc. Further, present-use designs strengthen stress areas assiduously with weighty reinforcement means. Additional support poles, rods, stakes and/or guy-lines to relieve the fabric of poorly diffused stress add further weight, complexity and expense.
The high cost of present-use structures is a fourth significant detriment. Because the supporting and covering functions are set in opposition, stresses inherent in large-scale design require framing members and fabrics not only heavier but also much more costly than necessary. Poles and rods are generally expensive components and heavier versions are even more costly to produce, ship and warehouse. Workmanship to cut and handle brawnier fabrics is more complicated and sewing is much more difficult. Reinforcing large areas as described increases manufacturing complexity and expense. Workmanship to attach myriad stakes, guy-lines and another anchoring means increases manufacturing costs while purchasing additional parts requires expensive outsourcing.
All prior-art large-scale fabric structures suffer a fifth and final drawback regarding their limited range of sizes and/or shapes. Present-use large structures are square or slightly rectangular; to erect larger structures or to utilize shapes other than these limited options introduces an entirely new level of complexity which is evidenced at outdoor events and the like where typically rented facilities accommodating larger groups of people involve an experienced full-time staff of many members and usually a full day for set-up or disassembly.
It is unfortunate that the designs of smaller-scale support structures, including their innumerable variants, can not be adapted for large-scale embodiments. Smaller-scale structures utilize bowed poles to place the fabric cover under tension; users skilled in the art recognize the difficulty and possible danger of bending enlarged support poles if adapted for use with larger-scale structures which typically use rigid and inflexible frame members. Also, smaller designs, if adapted, would lack basic functional capability: the simplest embodiments utilizing two or three support poles are undependable in ordinary winds without profuse anchoring, larger versions of these designs would be totally implausible. Designs of more elaborate smaller-scale embodiments utilize semispherical pole formations which employ arc trigonometry formulae that cannot be adapted if a low profile structure is required. These disadvantages, developed further in the following sections, effectively eliminate the possibility to adapt the myriad designs of small-scale embodiments for use as large-scale structures and today no such versions are recognized commercially.
Large-scale, freestanding tension structures which do not employ the inefficient support structure described previously have been disclosed in the prior art. My U.S. Pat. No. 5,343,887 describes a stable, lightweight, easy to assemble, portable fabric structure which eliminates weight-bearing support poles and rods by utilizing an end panel at each end, comprised of resilient strip material formed into a single hoop secured to flexible fabric covering and maintained in generally upright position by at least one spreader rod extending between the end panels. The end panels preferably have circular hoops, yet circles, by definition, are as tall as they are wide so by enlarging such structures the height and width are coequally increased. Thus the invention of my U.S. Pat. No. 5,343,887 is intended primarily or small-scale structures rather than for large-scale embodiments where height becomes a limiting factor.
A circular framing m
Horton Yvonne M.
Reising Ethington, Barnes, Kisselle, Learman & McCulloch, P.C.
LandOfFree
Portable fabric structure does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Portable fabric structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Portable fabric structure will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3039031