Abstract:
A portable sign including three legs movable between deployed and collapsed positions and a flexible covering bearing text, graphics or both includes a biasing mechanism urging the legs toward the deployed position. A support within the biasing mechanism secures three springs with the coils facing outward, one extension from each spring embedded in an upper support member and another extension movable within a plane tangential to a periphery of a lower support member and received by a hollow portion of one of the legs.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority as a continuation-in-part to U.S. patent application Ser. No. 11/087,145 filed on Mar. 23, 2005 now U.S. Pat. No. 7,392,610 and entitled “PORTABLE INFORMATION SIGNE DEVICE.” The content of the above-identified patent documents is hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure is directed, in general, to self-standing portable structures and, more specifically, to collapsible self-standing portable structures serving as warning markers and the like. 
     BACKGROUND 
     Collapsible or folding portable structures for cautionary, warning or alert purposes have been employed or proposed wherein a plurality of substantially rigid legs are hingedly connected at one end and biased to expand the opposite ends away from each other. Examples include U.S. Pat. No. 5,199,375 and U.S. patent application Publication No. 2006/0225319. The legs of such structures are generally covered with a flexible material such as canvas, plastic or fabric, which bears a warning message. In a deployed position, the structure rests on the ends of the legs that have been expanded away from each other, forming a pyramidal structure. 
     The biasing means within such structures is unsatisfactory. In U.S. Pat. No. 5,199,375, for example, torsional coil springs have ends each inserted into the ends of the tubular stays or legs, with the ends of two different springs being received by each leg and each spring having an end inserted in two adjacent legs. Such a biasing scheme suffers from the potential for an end of one or more springs to become dislodged from the leg into which that spring end was inserted, by coming out of the leg&#39;s end longitudinally, by the material of the tubular leg splitting, or as a result of some other circumstance. The different forces placed on the tubular leg by springs urging the leg in different directions may, for example, induce material fatigue and splitting of the leg at the end in which the spring ends are inserted. In such situations, an imbalance arises in the biasing and the structure may not deploy properly. In addition, failure of one of the springs may result in the biasing forces of the remaining two springs to cause the structure to deploy incorrectly. 
     The device disclosed in U.S. Patent Application Publication No. 2006/0225319 utilizes a biasing spring moving a spreader mechanism along a central rod, and is thus complicated and more expensive to manufacture and involves more parts that may malfunction. Thus, the existing biasing mechanisms for self-standing portable structures used to provide information, such warnings, advertisements, and/or general content, have not been successful in providing a simple structure that is inexpensive to manufacture, compact for storage and transportation, lightweight and easy to carry, quick and easy to erect, and quick and easy to collapse. 
     There is, therefore, a need in the art for an improved portable information sign device. 
     SUMMARY 
     To address the above-discussed deficiencies of the prior art, it is a primary object of the present disclosure to provide, for use in providing a portable information sign device employed to display an alert or warning message, an improved biasing mechanism. A portable sign including three legs movable between deployed and collapsed positions and a flexible covering bearing text, graphics or both includes a biasing mechanism urging the legs toward the deployed position. A support within the biasing mechanism secures three springs with the coils facing outward, one extension from each spring embedded in an upper support member and another extension movable within a plane tangential to a periphery of a lower support member and received by a hollow portion of one of the legs. 
     The foregoing has outlined rather broadly the features and technical advantages of the present disclosure so that those skilled in the art may better understand the detailed description that follows. Additional features and advantages will be described hereinafter that form the subject of the claims. Those skilled in the art will appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes. Those skilled in the art will also realize that such equivalent constructions do not depart from the spirit and scope of this disclosure in its broadest form. 
     Before undertaking the detailed description below, it may be advantageous to set forth definitions of certain words or phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or” is inclusive, meaning and/or; and the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like. Definitions for certain words and phrases are provided throughout this patent document, and those of ordinary skill in the art will understand that such definitions apply in many, if not most, instances to prior as well as future uses of such defined words and phrases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which: 
         FIG. 1  is a perspective view of an improved portable and collapsible information sign device according to one embodiment of the present disclosure; 
         FIG. 2  is a perspective view of an improved portable and collapsible information sign device according to one embodiment of the present disclosure; 
         FIG. 3  is a perspective view of a biasing mechanism within an improved portable and collapsible information sign device according to one embodiment of the present disclosure; 
         FIG. 4  is a top or plan view of a biasing mechanism within an improved portable and collapsible information sign device according to one embodiment of the present disclosure; and 
         FIG. 5  is a side elevation view of a biasing mechanism within an improved portable and collapsible information sign device according to one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1 through 5 , discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged device. 
       FIG. 1  is a perspective view, and  FIG. 2  is a bottom view, of an improved portable and collapsible information sign device according to one embodiment of the present disclosure. Sign  100  forms a three sided pyramid that in the exemplary embodiment has a height of about 12 to 18 inches, preferably about 18inches, and a width along one edge of the base of about 12 to 18 inches, preferably about 16 inches. Sign  100  includes a collapsible frame formed by three legs  102  biased towards a deployed position by biasing mechanism  104  at one end thereof. The opposite end of each leg  102  includes a tip  106 , with the sign  100  designed to rest on the ends of the tips  106  of all three legs  102  when deployed. A flexible plastic, canvas or fabric covering  108  covers the three legs from the biasing mechanism  104  along a length of the legs  102 . The covering  108  bears a warning or alert message for warning signs, although other (e.g., advisory or informational) messages are possible. A separate covering may be employed for the top of sign  100 , over the biasing mechanism  104 . 
     Covering  108  is affixed to an exterior of the biasing mechanism  104  by adhesive or other suitable means. A bottom periphery of covering  108  includes trim having grommets  110  therein for receiving the tips  106  at the ends of legs  102 . Tips  106  include a disk-shaped base (not visible in  FIG. 2 ) that allows a portion of tips  106  to extend through the grommets while keeping covering  108  under tension between the ends of the legs  102  and the biasing mechanism  104 . 
     Shown in the deployed position in  FIGS. 1 and 2 , in the collapsed position of sign  100  the legs  102  are rotated inward against the biasing force to a position in which the angles between the legs are substantially smaller, such that the legs are somewhat parallel to each other. A band  112  with a snap (or Velcro or similar fastening mechanism) may be provided to wrap around the legs  102  to maintain sign  100  in the collapsed position. A loop  114  for hanging the sign may also be provided. 
       FIG. 3  is a perspective view,  FIG. 4  is a top or plan view, and  FIG. 5  is a side elevation view of a biasing mechanism within an improved portable and collapsible information sign device according to one embodiment of the present disclosure. Biasing mechanism  104  includes a spring support  200  of molded, hardened rubber or plastic, in an upper piece  202  and a lower piece  204  held together by a bolt, locking washer and flanged nut in the exemplary embodiment. Support  200  securely holds three biasing springs  206 , one for each leg  102 , in position. Each biasing spring  206  is oriented with the annulus formed by the spring coil extending outward from a center (longitudinal) axis of the support  200  and the coils oriented tangentially to a perimeter of the support  200 . 
     Each biasing spring  206  includes one extension  208  oriented substantially parallel to a center (longitudinal) axis of support  200  and protruding through the upper piece  202  of support  200 , as well a second, longer extension  210  each received within the hollow body of one of the tubular legs  102 . Each extension  210  may be freely movable within the body of a leg  102 , or alternatively may be secured therein or secured to the exterior of the leg  102  along a length thereof. When the sign is in the deployed position, extensions  210  are at a marked angle to the center axis of support  200 . When the sign is in the collapsed position, the extensions (and the legs  102 ) are somewhat parallel to each other and to the center axis of support  200 . The biasing force thus results from expansion or tension on the spring coils rather than contract or compression (that is, the extensions force the coils to enlarge rather than contract when the sign&#39;s legs  102  are move from the deployed position to the collapsed position). 
     In the exemplary embodiment, each spring has coils with four windings approximately 1 inch in diameter, with extension  208  approximately 1 inch long and extension  210  approximately 3.5 inches long. The upper portion  202  of support  200  has a trefoil maximum radius of about 1 inch and a minimum radius of less than 0.75 inches, with a thickness of about 0.5 inches. The bottom portion  204  of support  200  has a radius of about 1 inch and a height of 1.0 to 1.25 inches. Upper and lower portions  202  and  204  of support  200  have recessed regions adapted to securely hold the springs  206  in position between the upper and lower portions  202  and  204 , with a lip on upper portion  202  extending over an outer edge of a top of each spring  206  while the extensions  210  project down outside the outer edge of the generally frustum-shaped bottom portion  204 . 
     With biasing mechanism  104 , legs  102  are not subjected to conflicting forces, such as when extensions from two different springs apply biasing force in different directions on a single leg. Accordingly, legs  102 , which may be made of simple rigid plastic, are less likely to split with biasing mechanism  104  that with other biasing schemes such as those described above. In addition, springs  206  have less force to overcome (since they are not counter-acting each other) and may therefore be smaller, and are less likely to fail due to fatigue. By anchoring each spring within support  200  and causing the biasing forces to be relative to support  200 , uniform biasing forces are applied to the legs  102  and less likelihood exists of shifting by the springs  206  to result in uneven biasing forces. 
     It should be noted that the orientation of springs  206  does not result in biasing force on legs  102  by extensions  210  in a direction radially outward from a center axis of support  200 , but instead at a substantially tangential angle. Allowing such biasing force still achieves deployment of the respective sign leg but simplifies mounting of springs  206  within block  200 , since no channels need be cut into block  200  to allow for movement of extensions  210 . Simple annular recesses may be formed within support  200  for receiving the coils of springs  206 , with extensions  210  extending outside the support  200 . Upper piece  202  may have a lip protruding down over springs  206  to help retain the springs securely in position. 
     Although the present invention has been described in detail, those skilled in the art will understand that various changes, substitutions, variations, enhancements, nuances, gradations, lesser forms, alterations, revisions, improvements and knock-offs of the invention disclosed herein may be made without departing from the spirit and scope of the invention in its broadest form.