Patent Application
20100011520
1. Field of the Invention
The present invention relates to portable wheelchair ramps, and more particularly to lightweight ramps in which unequally convolved fiber reinforced panels are joined to each other such that the more tightly folded panel forms a varying set of support contacts with the flexing of the outer support panel as the wheelchair is translated thereover.
2. Description of the Prior Art
The accommodation and assistance for those that are handicapped has been a constant focus of all civilized societies, to a point where the current architecture of our public places invariably includes structures that facilitate the mobility of those that are confined to a wheelchair. These concerns are expressed in various local ordinances and also in our general laws, as for example in the statutory enactments of the Americans with Disabilities Act [ADA], with the result that virtually all public places are easily traversed by those on wheeled carriages. Simply, our drive for personal independenc has compelled all sorts of conveniences in public places that accommodate the handicapped.
The same regulatory compulsions, however, face a more difficult economic challenge when confronted by the interests of privacy of individual households where the cost cannot be distributed or shared. Accordingly, private residences have had little regulatory attention other than regulations that deal with the basic concerns over health and safety. The age distribution of our residential inventory and the strongly imbedded notions of individual privacy resulted in a structural mix that rarely fits wheelchairs.
Thus even if the handicapped person selects a residence that has some of the favorable aspects, e.g., all on a single floor with rolling paths from the garage to the residence, and so on, old structural habits like door sills persist that for one reason or another render wheelchair transit difficult. This, of course, then creates a demand for various ramps and the like, but the transitory nature of all human contact does not just confine the needs for wheelchair mobility to one's own residence alone. Those that are handicapped need to consider their social ventures that lead into residences of others that are not so encumbered and thus the need for light, easily transported ramps.
In the past various ramp structures were devised that in one manner or another form a bridging structure between the varying levels of the floor, exemplified by the teachings of U.S. Pat. No. 5,946,756 to Mapp; and U.S. Pat. No. 5,324,004 to Richardson. While suitable for the purposes intended, each of these prior examples entails a three dimensional structure that obtains its strength from its monococque or semi-monococque configuration which inherently renders the ramp configuration both bulky and stiff and therefore difficult to carry.
Alternatively, foldable and articulated ramp structures have been proposed, as exemplified in the teachings of U.S. Pat. No. 7,001,132 to Koretsky et al.; U.S. Pat. No. 6,698,998 to Koretsky; U.S. Pat. No. 6,343,908 to Oudsten et al.; and U.S. Pat. No. 4,864,673 to Adaway et al. Each of these references, and similar others, while again suitable for the purposes intended, describe fairly complex folding ramp structures that are deployable by unfolding a bridging structure for a wheelchair either at the entrance of a vehicle or across an obstruction.
These bulky and complex features of the prior art ramp structures are particularly inconvenient in settings where the wheelchair confined person is simply a visitor in someone else's home under circumstances where the deployment complexity and/or necessary structural accommodation present an excessive burden to the host. Simply, the imposition of these burdens are often the primary obstacle to a full social life of an invalid who, quite often, simply elects to remain at home rather than impose on others.
In all their general configurations the prior art ramp structures are necessarily bulky and therefore difficult to store and/or transport and thus their use is limited to those applications to which they are directed. A lightweight, easily carried and easily deployed ramp structure adaptable to a wide range of transit impediments is therefore extensively desired and it is one such ramp structure that is disclosed herein.
Accordingly, it is the general purpose and object of the present invention to provide a layered ramp structure in which convolved fiber reinforced polymeric panels are joined to an outer panel to form an intermediate bridging support for a wheeled carrier traversing the outer panel.
Other objects of the invention are to provide a lightweight ramp structure in which a larger upper panel is supported by one or more convolved lower panels dimensioned to expose an adhesive strip along the underside of the outer panel edge for releasable contact to the impeding surface across which the ramp is deployed.
Yet further and additional objects of the invention shall become apparent upon the inspection of the illustrations and text that now follow.
Briefly, these and other objects are accomplished within the present invention by providing a generally rectangular fiber reinforced polymeric outer panel of a planform width generally greater than the base of a wheelchair which is then adhesively mounted along its center line onto the several spines or ridges of two or more longitudinally convolved lower panels. Each of these lower panels is again formed of a fiber reinforced polymeric material structure dimensioned substantially smaller than the outer panel and bent by heat application to form a generally V-shaped section.
Preferably, the segments on either side of the fold in each of the lower panels are each dimensioned to a transverse dimension that is somewhat greater than the typical height of a wheelchair impediment, e.g., the height of the door step or the entryway sill, thus providing an inclined bridging surface when the impeding edge is received in the fold. The underside of the other edge portion of the outer panel that then extends beyond the other segments of the lower panels onto the impediment's upper horizontal surface is, in turn, provided with a covered adhesive strip that is then exposed and adhered to this surface once properly aligned.
In this form the wheelchair confined visitor, or the thoughtful host, are able to temporarily modify the several problematic impediments in the residence by a device that is easily removed once the visit ends. When not in use the simplicity of the impediment bridging structure and its flexible form lend themselves to easy and convenient storage either in corners behind other stored objects or within the elements of a folded wheelchair.
Those skilled in the art will appreciate that in both the panel components of the inventive bridging device the material structures used are fiber reinforced polymeric panels selected from the many known thermoplastic polymer groups which can be bent when heated to the desired fold shapes and thereafter fused together by further application of heat to the juncture between the apex of the lower panels and the outer panel to which they attach. This last heat application, in particular, consolidates the panel juncture into a fairly robust mass of fiber reinforced matter that provides structural stiffness to all the joined components, thus reinforcing the bridging segment of the lower panels while also limiting the outer surface to smooth bends on either side of the apex that expand into load induced undulations that are easily traversed.
In this manner a lightweight, inexpensive and easily carried and ramp structure is devised which can be easily deployed. These structural benefits can be easily implemented in various manners and with various polymeric materials with the necessary panel stiffness assured by the appropriated selection of the reinforcing fiber thickness, its weave and its density.
As shown in
A pair of lower panels 30-1 and 30-2, each of a planform that is less than one half of the planform dimensions of panel 20 but formed of a material structure generally like the above described panel, are each convolved by heat application to form a central apex or ridge 31 that is thereafter bonded by heat application once more in spaced alignment to the underside of the outer panel 20 along an axis generally bisecting its planform. By virtue of this heat bonding of the ridges 31 of each of the lower panels 30-1 and 30-2 to the underside of panel 20 a consolidated sectional mass is developed, shown as a sectional mass 35, which both acts to stiffen the adjacent portions 23 and 24 of panel 20 while also fixing the relative alignment of the portions 33 and 34 of each of the lower panels to project in a V shape therefrom.
A releasably covered adhesive strip 26 mounted on the underside of the outer panel 20, along one longitudinal edge 27 thereof, is then useful to adhere the panel to the door sill or doorstep surface DS once the sill or step edge SE is received within the inner convolution of the ridges 31 and when thus affixed the opposite portion 34 then forms a bridging ramp from the sill edges SE to the lower surface LS in front of the sill. In this manner a stiffening reinforcement of panel 20 is obtained as the wheelchair WC is rolled thereover and thus transitioned across the impediment of the sill.
By particular reference to
Those skilled in the art will appreciate that the foregoing ramp structure utilizes to advantage polymers and glass that are currently part of our recycling stream and is thus essentially unobtrusive. Moreover, the use of one common panel material structure throughout simplifies the fabrication process of this assisting device that is easily carried, mounted and thereafter removed.
By further reference to
Obviously, many modifications and variations can be effected without departing from the spirit of the invention instantly disclosed. It is therefore intended that the scope of the invention be determined by the claims appended hereto.
This application obtains the benefit of the earlier filing date of U.S. Provisional Application No. 61/135,092 filed on Jul. 16, 2008.
| Number | Date | Country | |
|---|---|---|---|
| 61135092 | Jul 2008 | US |
