Patent Publication Number: US-6663921-B1

Title: Collapsible Christmas tree

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to decorative structures, and more particularly to a collapsible Christmas tree that is easy to erect, easy to collapse, compact for storage, and whose structure has a decorative shape when erected. 
     2. Description of the Background Art 
     During the holiday seasons, homes are commonly adorned in and out with festive decorations. One common decoration is the artificial Christmas tree. 
     Artificial trees are designed and manufactured in both indoor and outdoor varieties. Indoor and outdoor type artificial trees each suffer several disadvantages. Indoor trees, for example, require large amounts of storage space because they are generally formed from many interconnecting components that have fragile branches and pine needles attached thereto for decoration. Additionally, the components, because of their interconnecting complexities, require a substantial amount of time to setup. 
     One type of outdoor artificial tree is essentially a conical wire frame structure, to which decorations can be attached. The wires used in such frames is typically straight, and so the frame structures are generally plain, and apart from their conical shape and attached decorations bear little resemblance to a real tree. Further, the wire frame structures are typically formed as a single unit, and therefore require a relatively large amount of storage space when not being displayed. 
     What is needed, therefore, is a decorative structure that is suitable for indoor and outdoor use, that requires little assembly or disassembly, is compact and easy to store, and has a structure with a decorative shape suggestive of a Christmas tree. 
     SUMMARY 
     The present invention overcomes the problems associated with the prior art by providing a decorative structure that is easy to erect and to collapse, is compact for storage, and whose structure has a decorative shape suggestive of a Christmas tree. 
     The decorative structure includes a length of strand material and a twisting member. The strand material includes a plurality of individual strands that are twisted with respect to one another, and are fixed with respect to one another near first ends of the strands. The twisting member includes a plurality of apertures formed therein, each adapted to receive a respective one of the individual strands therethrough. In a particular embodiment, the decorative structure resembles a Christmas tree, and the twisting member is a disc defining a separate aperture for each strand of the strand material. In a more particular embodiment, at least one of the apertures is oblong in shape. 
     To open the tree the twisting member is advanced from a position near second ends of the strands toward the first ends of the strands, causing the strand material to unwind. When unwound, the strands retain a decorative helical shape, suggestive of the layered branches of a Christmas tree. To collapse the tree, the twisting member is advanced from a position near the first ends of the strands toward the second ends of the strands, causing the strand material to wind up. 
     In a particular embodiment, the decorative structure includes a coupling device disposed near the first end of the strands for fixing the strands together with respect to one another. In a more particular embodiment, the strand material is strand steel, and the coupling device is a weld. In still a more particular embodiment, the strand steel includes a straight center strand which is cut substantially shorter than the remaining strands of the strand material. 
     Optionally, the decorative structure includes a cover (e.g., a metal cap) for covering the first ends of the strands. In a particular embodiment, the cover is adapted such that a decorative object can be mounted thereto. 
     An optional strand retainer holds the strands in a wound state. Examples of strand retainers include, but are not limited to, an annular ring having and inner diameter slightly larger than the outer diameter of the wound strands, and/or a removable strap that can be wrapped around the wound strands. 
     An optional twisting member retainer prevents the strands from disengaging the twisting member. Possible twisting member retainers include, but are not limited to, a separate device (e.g., a grommet, a clamp, removable feet, etc.) coupled to at least one of the strands of the strand material, and/or a deformation (e.g., a bend, an enlargement) in at least one of the strands of the strand material. 
     Coating the individual strands, while not essential, protects the decorative structure, enhances the decorative appearance, and makes it easier to wind and unwind the strand material. In a particular embodiment, the coating is a white powder coating. Alternatively, the strands can be painted. 
     Attachment devices are provided for attaching decorations (e.g., Christmas lights, ornaments, etc.) to the decorative structure. In a particular embodiment, the attachment device is a detachable clip having a first end for attaching to one of the individual strands and a second end for attaching to the decoration. The attachment devices, as well as other aspects of the invention even if not explicitly stated, are not considered to be an essential element of the present invention. For example, the decorative structure of the present invention can be used with a decorative slip-over cover, thereby eliminating the need for attachment devices. 
     In another particular embodiment, the decorative structure includes a plurality of helical strands, each strand having a first end and a second end, a coupling device fixing the strands together near the first ends of the strands, and a positioning device adapted to selectively position the second ends of the strands a spaced distance from one another. The positioning device is further adapted to selectively position the second ends of the strands in a close together relationship, for example for storage. 
     A method for erecting a decorative structure is also described. The method includes the steps of providing a length of strand material including a plurality of individual strands twisted with respect to one another, and fixed together at a first end with respect to one another. The method further includes unwinding the strands of the strand material from a second end to the first end using a twisting member. The twisting member defines a plurality of apertures, each aperture adapted to receive a respective one of the individual strands therethrough. The method of erecting a decorative structure further includes an optional step of releasing a strand retainer, either prior to or during the step of unwinding the strands. In a particular method, the step of unwinding the strands includes twisting the twisting member about a longitudinal axis oriented generally inline with the strand material. In yet another particular method, the method of erecting a decorative structure includes standing the decorative structure upright, such that the decorative structure is supported by the unwound ends of the strands. 
     A more particular method for erecting a decorative structure further includes rewinding the strands of the strand material by moving a twisting member from the first end of the strand material toward the second end of the strand material, while rotating said twisting member about a longitudinal axis of said strand material. Optionally, the method further includes the step of applying a retainer near the second end of said strand material to prevent the unwinding of the strands. 
     A method for manufacturing a decorative structure is also disclosed. The method includes the steps of providing a length of strand material including a plurality of individual strands twisted with respect to one another, coupling the strands with respect to one another near a first end of the strand material, providing a twisting member having a plurality of apertures formed therein, and positioning a second end of each of the individual strands in a respective one of the apertures of the twisting member. 
     The method of manufacturing the decorative structure further includes an optional step of providing a cover for covering the first end of the strands, an optional step of providing a strand retainer for retaining the strands in a wound state, and an optional step of providing a twisting member retainer for retaining at least one individual strand in a respective aperture of the twisting member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is described with reference to the following drawings, wherein like reference numbers denote substantially similar elements: 
     FIG. 1 is a perspective view showing an embodiment of a decorative structure of the present invention in a display state; 
     FIG. 2 is a front plan view of a first end of the decorative structure of FIG. 1; 
     FIG. 3 is a cross-sectional view taken along section line A—A through the twisting member of FIG. 2; 
     FIG. 4 is a partially exploded view showing the decorative structure of FIG. 1 in a storage state; 
     FIG. 5 is a top plan view of a fastening clip for fastening decorations to the decorative structure of FIG. 1; 
     FIG. 6 is a flowchart summarizing one method of erecting the decorative structure of FIG. 1; 
     FIG. 7 is a flowchart summarizing one method of collapsing the decorative structure of FIG. 1; and 
     FIG. 8 is a flowchart summarizing one method of manufacturing the decorative structure of FIG.  1 . 
    
    
     DETAILED DESCRIPTION 
     The present invention overcomes the problems associated with the prior art, by providing a collapsible decorative structure (e.g., a Christmas tree) that is compact and easy to store, requires little assembly or disassembly, and has a structure that retains a decorative appearance when erected. In the following description, numerous specific details are set forth (e.g., number of individual strands in strand material, use of steel strand material, etc.) in order to provide a thorough understanding of the invention. Those skilled in the art will recognize, however, that the invention may be practiced apart from these specific details. In other instances, details of well known processes (e.g. strand material fabrication, powder coating, etc.) have been omitted, so as not to unnecessarily obscure the present invention. 
     FIG. 1 shows a decorative structure  100  according to one embodiment of the present invention. Decorative structure  100  includes a length of strand material  102 , that is composed of a plurality of individual strands  104 ( 1 - 7 ), each having a first end  106 ( 1 - 7 ) and a second end  108 ( 1 - 7 ). Decorative structure  100  further includes a twisting member  110 , an end cover  112 , a strand retainer  114 , and a plurality of twisting member retainers  116 ( 1 - 6 ). In addition, decorative structure  100  includes a decoration  118  draped around strands  104 ( 1 - 6 ), and a decorative cap  120  adapted to mount over end cover  112 . 
     In the erected state shown in FIG. 1, decorative structure  100  is supported on a support surface  122  by the second ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ). Individual strands  104 ( 1 - 6 ) are fixed in position with respect to each other at their first ends  106 ( 1 - 7 ), which are wound around straight center strand  104 ( 7 ). Twisting member  110  defines a plurality of apertures  124 ( 1 - 7 ), through each of which a respective one of strands  104 ( 1 - 7 ) passes. When twisting member  110  is positioned near first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ), second ends  108 ( 1 - 7 ) are positioned in a spaced apart relationship by twisting member  110 . As twisting member  110  is moved toward second ends  108 ( 1 - 7 ), as will be described in greater detail hereinafter, second ends  108 ( 1 - 7 ) are drawn into a close together relationship. Thus, twisting member  110  functions as a positioning device that selectively positions second ends  108 ( 1 - 7 ) in either a spaced apart relationship (erected state) or a close together relationship (collapsed state). 
     Cover  112  is a metal cap that covers first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ) for safety and aesthetics. Strand retainer  114  keeps strands  104 ( 1 - 7 ) in a wound relationship when decorative structure  100  is in the collapsed state, as will be described below. In this particular embodiment, strand retainer  114  is an annular ring having an inner diameter slightly larger than the outer diameter of strand material  102  in its wound state. Decoration  118  represents Christmas lights, garland, and the like which can be draped around or fastened to decorative structure  100 . Decorative cap  120  is adapted to detachably mount over cover  112 , to facilitate the use of a variety such decorations. Optionally, decorative cap  120  and cover  112  can be formed integrally to reduce the number of parts. 
     In the present embodiment, decorative structure  100  is a Christmas tree, and will hereinafter be referred to as such. It should be noted, however, that the decorative structure described herein can be used for other occasions or purposes (e.g., theater scenery, landscape decorations, etc.), in addition to the Christmas tree embodiment shown. 
     Also in the present embodiment, strand material  102  is formed from 0.6″ strand steel having six twisted strands (e.g., strands  104 ( 1 - 6 )) and a straight center strand (e.g., strand  104 ( 7 )). Manufacturing Christmas tree  100  from strand steel is inexpensive because strand steel is readily available in industry (e.g., in concrete reinforcement), as well as, provides durability to tree  100 . Additionally, Christmas tree  100  can be manufactured from scrap pieces (e.g. a few feet long) which are of little or no value for conventional strand steel applications. It should also be noted that alternate materials may be used to manufacture tree  100  including, but not limited to, molded plastics, other metals, wood, and/or fiber products. 
     The present invention provides several advantages over the prior art. One advantage is that Christmas tree  100  can be quickly and easily erected and collapsed. Twisting member  110  facilitates the winding and unwinding of strand material  102 . When twisting member  110  is advanced from a position near first ends  106 ( 1 - 7 ) to a position near second ends  108 ( 1 - 7 ) of strands  104 ( 1 - 7 ), and twisting member  110  is simultaneously rotated about a longitudinal axis of the strand material, the individual strands  104 ( 1 - 6 ) of strand material  102  are caused to wind up into a twisted relationship. Conversely, advancing twisting member  110  from second ends  108 ( 1 - 7 ) to first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ) causes strands  104 ( 1 - 7 ) to unwind into the open relationship depicted in FIG.  1 . 
     It should be noted that twisting member  110  is not an essential element of the present invention. For example, an alternate tree can be formed, without a twisting member, from a plurality of helical (or otherwise wavy) strands fixed together near their first ends by a coupling device (e.g., a weld, clamp, etc.). A simple solid structure (e.g., a cone, a pyramid, a sphere, etc.) placed between the helical strands would serve as a positioning device to hold the second ends of the strands in a spaced apart relationship, instead of the twisting member. Thus, to erect the alternative tree, the user would simply wedge the positioning device up between the strands near enough to the fixed first ends to obtain the desired spacing of the second ends. Similarly, to collapse the alternate tree, the user need only remove the positioning device. Because this embodiment does not include a twisting member, the helical strands could not be wound and unwound, but would merely be gathered together for storage. Optionally, the positioning device can be mounted to or supported by a center strand. As another option, the positioning device can include grooves for receiving and positioning the individual strands. 
     In its wound state, tree  100  can be easily transported and stored. As previously described, prior art artificial trees require substantial storage space. Tree  100 , when in its wound state, is not significantly larger than the strand steel cable from which it is formed (see FIG.  4 ). Therefore, tree  100  requires significantly less storage space than conventional artificial Christmas trees. 
     Another advantage provided by tree  100  is that strands  104 ( 1 - 6 ) retain their twisted shape when unwound. The helical shape of strands  104 ( 1 - 6 ) provide a wavy appearance suggestive of the boughs of a pine tree. This is a significant improvement over the straight wire frame structures of the prior art. 
     Strands  104 ( 1 - 7 ) are individually coated for appearance and protection. The inventor has determined that strands  104 ( 1 - 7 ) can be easily powder coated when tree  100  is in its erect state. Powder coating strands  104 ( 1 - 7 ) adds a durable, colorful finish, and provides rust protection. Optionally, strands  104 ( 1 - 7 ) can be individually painted to obtain similar benefits. 
     Strands  104 ( 1 - 7 ) can be powder coated or painted in a variety of colors depending on intended use and individual preference. For example, tree  100  is powder coated white to suggest a snow covered Christmas tree. As another example, tree  100  could be painted green, suggestive of an evergreen tree. Obviously, if tree  100  was formed from a plastic, the plastic could be colored to give the tree a colored appearance. 
     To summarize, Christmas tree  100  can be wound up for storage as follows. First, decoration  118  is removed from cap  112 . Next, individual strands  104 ( 1 - 6 ) are wound together by advancing twisting member  110  toward free second ends  108 ( 1 - 7 )) of strands  104 ( 1 - 6 ). As twisting member  110  is advanced along the length of strand material  102 , twisting member  110  is twisted about the longitudinal axis of strand material  102 . Twisting member retainers  116 ( 1 - 6 ) prevent twisting member  110  from coming off of second ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ). Finally, strands  104 ( 1 - 6 ) are secured in their twisted state by sliding strand retainer  114  from first ends  106 ( 1 - 7 ) to a position near second ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ) to prevent the unraveling strands  104 ( 1 - 6 ). 
     From its wound state, tree  100  is erected as follows. First, strand retainer  114  is released by moving strand retainer  114  from second ends  108 ( 1 - 6 ) to a position near first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ). Next, advancing twisting member  110  toward first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ) causes strand material  102  to unwind. When twisting member  110  reaches a position near first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ), second ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ) are held in an open, spaced apart relationship, such that second ends  108  of strands  104 ( 1 - 6 ) can support tree  100  on ground  122 . Finally, tree  100  can be decorated by fastening (e.g. with attachment device  500 , clips, hooks, etc.) decoration  118  to strands  104 ( 1 - 7 ), and by placing decorative cap  120  over cover  112 . 
     FIG. 2 is a front plan view of a portion of collapsible tree  100  near first ends  106 ( 1 - 7 ). There are several notable features of tree  100 , which are clearly shown in FIG.  2 . First, center strand  104 ( 7 ) is shown straight and cut substantially shorter than the remaining individual strands  104 ( 1 - 6 ) because of its non-helical shape. Additionally, individual strands  104 ( 1 - 6 ) are twisted around center strand  104 ( 7 ) near first ends  106 ( 1 - 7 ). Retaining at least a portion of center strand  104 ( 7 ) is beneficial to retain proper position and winding of helical strands  104 ( 1 - 6 ). Finally, in the present view twisting member  110  is shown as a flat disc, having each of strands  104 ( 1 - 7 ) passing therethrough, and is centered about a longitudinal axis of strand material  102  passing through center strand  104 ( 7 ). 
     FIG. 3 is a cross-sectional view taken along section line A—A of FIG. 2 showing twisting member  110  in greater detail. In the present embodiment, twisting member  110  is formed (e.g., machined, molded, etc.) from plastic, but it should be understood that alternate materials including, but not limited to, metal, fiberglass, wood, etc. may be used. Twisting member  110  is a round disc, having apertures  124 ( 1 - 6 ) situated around the perimeter and aperture  124 ( 7 ) located in the center. Apertures  124 ( 1 - 6 ) are oblong to facilitate easier winding and unwinding of strands  104 ( 1 - 6 ), which vary in separation from center as they travel through their respective apertures  124 ( 1 - 6 ) when twisting member  110  is advanced along strand material  102 . Center aperture  124 ( 7 ) is circular because center strand  104 ( 7 ) is straight. Optionally, twisting member  110  can be manufactured with finger grooves (not shown) about the perimeter, to make twisting member easier to grip. 
     FIG. 4 shows a partially exploded view of Christmas tree  100 , in its wound up, collapsed state. Cover  112  is removed from first ends  106 ( 1 - 7 ) to expose a weld  402 . Weld  402  mechanically couples strands  104 ( 1 - 7 ) together at first ends  106 ( 1 - 7 ). Weld  402  is most easily formed during manufacture using an oxy-acetylene torch, wherein the strand material  102  is melted, but could be formed with alternate methods including, but not limited to, stick, MIG, and TIG welds, or brazing. Alternately, strands  104 ( 1 - 7 ) can be fixed together using a clamp or strap secured around first ends  106 ( 1 - 7 ), and/or a suitable epoxy. 
     Substitutions for other components of tree  100  can also be made without departing from the scope of the invention. For example, a deformation (e.g., a bend, extrusion, melted portion, etc.) in at least one of strands  104 ( 1 - 6 ) to retain twisting member  110  on strands  104 ( 1 - 7 ) could be substituted for twisting member retainers  116 ( 1 - 6 ). As another example, a strap wrapped around strands  104 ( 1 - 6 ) near second ends  108 ( 1 - 7 ) could be substituted for strand retainer  114 . 
     FIG. 5 shows a top view of an attachment device  500  for attaching decorations (e.g., decoration  118 ) to tree  100 . Attachment device  500  includes a lower jaw  502  and an upper jaw  504  coupled to lower jaw  502  by a pin  506 . Lower jaw  502  includes a strand clamp  508 , a lower pin support  510 , and a lower tooth  512 . Similarly, upper jaw  504  includes an upper pin support  514  and an upper tooth  514 . Lower tooth  512  and upper tooth  514 , when together, define a small guideway  518  and a large guideway  520  for grasping decorations of various sizes. Compression is placed on lower tooth  512  and upper tooth  514  by a spring (not shown) acting about pin  506  on lower jaw  502  and upper jaw  504 . 
     In the current view, attachment device  500  is a detachable clip and can selectively engage one of individual strands  104 (x) when tree  100  is erected by pressing strand clamp  508  onto strand  104 (x). Lower pin support  510  engages upper pin support  514  at pin  506 . When attached to tree  100 , upper jaw  504  is pivotal about pin  506 , permitting upper tooth  516  to separate from lower tooth  512  when force is applied to a pressure end  522  of clip  500 . With upper jaw  504  in an open position, decorations can be retained in small guideway  518  or large guideway  520 , when upper jaw  504  is released. The number of clips required depends on various factors such as the size of the tree, the character of the decorations, the environment, etc. 
     FIG. 6 is a flowchart summarizing one method  600  of erecting decorative structure  100  according to the present invention. In a first step  602 , strands  104 ( 1 - 6 ) are released by moving strand retainer  114  toward first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 7 ). Then, in a second step  604 , strands  104 ( 1 - 6 ) are unwound by advancing twisting member  110  toward first ends  106 ( 1 - 7 ) of strands  104 ( 1 - 6 ). Note that strand retainer  114  can be moved either before or as twisting member  110  is advanced. 
     FIG. 7 is a flowchart summarizing one method  700  of collapsing decorative structure  100  according to the present invention. In a first step  702  strands  104 ( 1 - 6 ) are wound up by advancing twisting member  110  toward the free ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ). Next, in a second step  704 , strands  104 ( 1 - 6 ) are secured with strand retainer  114  to prevent unraveling, by sliding strand retainer  114  from a position near first ends  106 ( 1 - 7 ) to a position near second ends  108 ( 1 - 6 ). 
     FIG. 8 is a flowchart summarizing one method  800  of manufacturing decorative structure  100  according to the present invention. In a first step  802 , a length of strand material (e.g., strand steel) is provided. Then in a second step  804 , strands  104 ( 1 - 7 ) are fixed together (e.g., welded, clamped, strapped, etc.) near first ends  106 ( 1 - 7 ). Next, in a third step  806 , strand retainer  114  is provided, and slid over second ends  108 ( 1 - 7 ) of strands  104 ( 1 - 7 ) to prevent individual strands  104 ( 1 - 7 ) from unraveling. Then, in a fourth step  808 , twisting member  110  is provided for winding and unwinding strands  104 ( 1 - 6 ) of strand material  102 , and in a fifth step  810 , second ends  108 ( 1 - 7 ) of strands  104 ( 1 - 7 ) are positioned in respective apertures  124 ( 1 - 7 ) of twisting member  110 . Finally, in a sixth step  812 , at least one of twisting member retainers  116 ( 1 - 6 ) are attached near second ends  108 ( 1 - 6 ) of strands  104 ( 1 - 6 ) to retain twisting member  110  on strands  104 ( 1 - 6 ). 
     The description of particular embodiments of the present invention is now complete. Many of the described features may be substituted, altered, or omitted without departing from the scope of the invention; For example, an alternate strand retainer  114  (e.g., a removable strap), may be substituted for the annular ring embodiment shown. As another example, the decorative structure can be used to display decorations (e.g., birds, fruit, etc.) other than Christmas decorations. These and other deviations from the particular embodiments shown will be apparent to those skilled in the art, particularly in view of the foregoing disclosure.