Abstract:
An umbrella frame provides a stable and enduring support for an umbrella canopy while also allowing canopies of varying shapes and sizes to be mounted thereto. The umbrella frame includes a pair of hub members mounted about a pole member wherein each hub member has a plurality of slots formed in its outer perimeter. Ribs and struts are pivotally secured to the hub members using hub connectors which are removably secured to the hub slots so as to allow the size and shape of the attached canopy to be readily varied. The struts are also pivotally secured to the ribs by a collar member which helps prevent damage to the overlying canopy. The umbrella frame is rotatable about its axis in both the extended and retracted positions.

Description:
FIELD OF THE INVENTION 
     This invention relates to umbrellas, and more particularly to a durable and versatile umbrella frame for encountering abusive weather conditions. 
     BACKGROUND AND SUMMARY OF THE PRESENT INVENTION 
     Outdoor umbrellas are employed to shield people from the sun, wind, rain, and other elements of nature. As such, they are intentionally designed to withstand these elements. Nevertheless, damage to the framework of an umbrella can and does occur for many reasons, particularly to umbrellas in geographical areas of severe and unexpected weather, as well as umbrellas which have been improperly installed. Many prior art umbrellas suffer the disadvantages of not being able to withstand harsh weather as well as not being capable of simple repair when damage does occur. For example, an umbrella having static wire, rigid line and an unbalanced construction at the rib and strut pivot point will wear and often break when extreme forces are applied over time. Because the static or rigid line connects a plurality of ribs and struts at the upper and lower central hubs, any compromise of this entity will mean the collapse of the entire canopy assembly. Further, once an umbrella is damaged, it is often more expensive and difficult to repair the umbrella than to have it replaced. 
     For umbrellas having individual pivotal connections between the upper rib and lower strut assembly, the unbalanced nature of the movement at the pivot point in relation to the upper and lower central hubs causes unnecessary wear on the pivot junction as well as to the static wire or rigid line which connects the canopy rib assembly to the central hubs. This wear is undesirable and is aggravated over time by the stresses of both man and nature. 
     For umbrellas having individual pivotal connections between the upper rib and lower strut assembly by means of a vertically configured bracket individually, the existing plastic brackets protrude over the top of the canopy assembly providing a point of friction between the fabric of the canopy and the rigid protrusion of the pivot bracket. This creates excessive wear on a fabric canopy and often creates holes in the fabric canopy. 
     Various umbrella frames are described, for example, in the following U.S. Pat. Nos.: D25,368 to Sparry; D56,043 to Weinberg et al.; U.S. Pat. No. 2,336,116 to Morando; U.S. Pat. No. 3,177,882 to Militano; U.S. Pat. No. 4,368,749 to Lindler et al.; U.S. Pat. No. 4,834,126 to Sweet, Jr.; and U.S. Pat. No. 5,715,853 to Lin. None of these umbrella frames shows the connection of a central hub with a secondary hub in a manner which allows for the quick exchange of components so as to allow the customization of the size and shape of the canopy member atop the umbrella frame. 
     By the present invention, there is provided a durable outdoor umbrella frame that will withstand extreme forces and that may be quickly, easily and inexpensively repaired. The present invention is also easily modified to accommodate umbrella canopies of different sizes and shapes. The present invention includes a pair of hub members having a set of slots about their radial edges for receiving a combination of hub connector joints. A matching number of ribs and struts are pivotally secured to each hub by these joints, and the struts are pivotally secured to the ribs by collar members. The hub connector joints and the collar members are easily mounted and replaced, and assist in the smooth operation of the umbrella frame. Additionally, the collar members maintain a low profile so as to avoid contacting and thereby potentially damaging a mounted canopy. 
     It is thus one object of the present invention to provide an umbrella frame which can be easily manipulated to allow the attachment of canopies of varying shapes and sizes. 
     It is another object of the present invention to provide an umbrella frame capable of withstanding extreme temperature, wind and other weather conditions. 
     It is a further object of the present invention to provide an umbrella frame capable of simple rotation. 
     It is another object of the present invention to provide an umbrella frame having easily replaceable and interchangeable parts. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partial exploded front elevational view in partial cross-section of the umbrella frame assembly of the present invention, with different positions of the frame assembly shown in phantom and dashed lines. 
     FIG. 2 is a partial front elevational view in partial cross-section of the umbrella frame assembly of the present invention, shown with a double pulley system installed. 
     FIG. 3 is an exploded perspective view of the hub members of the present invention, showing the hub connector joints. 
     FIG. 4 is an exploded perspective view of the collar member of the present invention. 
     FIGS. 5 through 9 are top schematic views showing examples of different canopy shapes which may be employed with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in FIGS. 1 through 9, there is provided an umbrella frame assembly  10  for use in easily and quickly supporting a variety of shapes and sizes of umbrella canopies. The frame assembly  10  is durable and weather resistant, and includes a longitudinally extending pole member  12  which can be made of wood, aluminum or other material. In one embodiment, the pole member is made of  40  gauge aluminum. The pole member  12  has a top end  14  and a bottom end  16 . The bottom end  16  may be easily secured to the ground or any means of vertical affixment or, a reinforced concrete base, for example, such as one having a star knob and hitch pin. A main hub member  18  having a central cavity  20  extending axially therethrough is secured about the central pole member and is slidable between the top  14  and bottom  16  ends of the pole member. The main hub member  18  is also capable of rotating about the pole member axis. In one embodiment of the invention, as shown in FIGS. 1 and 2, the main hub member  18  is provided with a substantially “hour glass” shaped base portion  22  having upper  24  and lower  26  portions and a waist portion  28  which is of smaller diameter than the upper and lower portions. The base portion shape allows for simple hand manipulation of the hub member  18  up and down the pole member. 
     As shown in FIGS. 1 through 3, an upper or secondary hub member  30  is provided near the top end  14  of the pole  12 . The secondary hub member  30  is provided with a central cavity  32  extending axially therethrough, wherein the cavity includes a pole receiving portion  34  and a narrower upper portion  36  which extends through an interior wall  38  of the secondary hub member. The interior wall  38  maintains the hub member in position at the top end  14  of the pole  12 . The hub members  18 ,  30  may be made of injection molded thermoplastic, such as DELRIN with TEFLON, for example, so as to resist rust, UV degradation, dry rot, and water damage. Other rigid and or flexible material may be used. 
     As shown in FIG. 1, a threaded bolt  15  extends from the central pole  12  through the narrow upper portion  36  of the secondary hub member central cavity  32 . A nut  17  tightened about the bolt  15  is capable of maintaining the secondary hub member  30  in substantially rigid position about the pole  12 . When desired, the nut  17  may be loosened so as to allow the secondary hub member to rotate about the pole axis. A finial or end cap  40  is also secured to the bolt  15  for aesthetic purposes once a canopy has been positioned atop the frame assembly. The end cap also maintains the fabric canopy in a secured central position. 
     As shown in FIG. 3, the main  18  and secondary  30  hub members are further provided with slots  42  formed at intervals about their respective radial edges  44 . The slots  42  are three sided and include a base  46 , a back wall  48 , and a pair of side walls  50 . The back wall faces radially outwardly from the hub members  18 ,  30  and the side walls extend outwardly from the slot back wall  48  at diverging angles. In one embodiment of the invention, the slots are approximately ¼ inch in depth and the slot back wall is approximately ¾ inches in width. 
     As shown in FIG. 3, hub connector joints  52  are insertable within the hub member slots  42  and may be secured therein by screws  54 , for example. The hub connector joints may be made of injection molded thermoplastic or stamped metal, for example. The hub connector joints are provided with a base portion  56  and a pair of substantially parallel side walls  58  which define an interior aperture  60 . The hub connector joints also have a back face  62  and a pair of corner walls  64  which extend outwardly from the back face  62  at diverging angles. The back face  62  and corner walls  64  mate respectively with the slot back wall  48  and slot side walls  50 . Thus, the angles with which the corner walls  64  and slot side walls  50  diverge from the back face  62  and slot back wall  48 , respectively, are substantially identical. In one embodiment of the invention, this angle is approximately 104 degrees. Providing the slots  42  with three walls  62 ,  64  and a base portion  56  ensures a snug fit of the hub connector joints within the hub member slots and helps prevent the joints  26  from twisting or displacing under stress. Further, the depth and width of the slots allow the hub connector joints to be readily secured and removed from within the slots using a screw  54 , as shown in FIG.  3 . While a screw member is shown as the means of attachment for the hub connector joints within the hub member slots, other forms of attachment may be employed, such as a machine threaded bolt, fitted notch or other element which allows the hub connector joints to be easily attached and removed. As shown in FIG. 3, the interior surface  66  of the hub connector joints  52  may be rounded and substantially U-shaped so as to provide clearance for rib and strut members, as described hereinafter. In the embodiment of the invention as shown in FIG. 3, the hub members  18 ,  30  are provided with eight slots  42  so as to accommodate up to eight hub connector joints  52 . Other #&#39;s of slots may be utilized as well. 
     As shown in FIGS. 1,  2  and  4 , rib members  70  are pivotally secured to the hub connector joints  52  of the secondary hub member  30 . The rib members  70  form the outer framework of the umbrella frame of the present invention. Strut members  80  are pivotally secured at a first end  82  to the hub connector joints  52  of the main hub member  18  and are pivotally secured at a second end  84  to the rib members  70  at a point near the approximate midpoint of the rib members. The strut members  80  provide support for the rib members when the umbrella frame is in the extended or open position. Pivotal attachment of the rib and strut members to their respective hub connector joints may be exacted using a single screw  54  extending through the hub connector joint and rib or strut member, machine threaded bolt, fitted notch or other like joinery that allows the hub connector joints to be easily replaceable. The rib and strut members may be made of aluminum or wood, for example. 
     As shown in FIG. 4, the strut members  80  are pivotally secured to the rib members  70  by a collar member  90 . The collar member  90  includes a pair of substantially parallel outer walls  92  and a central divider wall  94  which combine to define an upper channel portion  96  and a lower slot portion  98  on opposite sides of the divider wall  94 . The upper portion  100  of the collar member outer walls  92  which define the channel portion  96  includes outwardly diverging side edges  102  and a substantially flat top edge  104 . The channel portion  96  may have a substantially rounded interior surface  106  adapted for receiving the rib members. When the rib members are in a substantially different shade the channel portion  96  may be adapted to match shape. As shown in FIG. 4, the channel portion interior surface  106  extends around over one half the circumference of the rib member. As shown in FIG. 4, the rib members  70  may be secured within the collar member channel portion  96  by a screw  91  and nut  93 . The substantially flat top edge  104  of the collar member avoids contact with the umbrella canopy which is positioned over the rib members and thereby helps prolong the life of the canopy employed. The strut members  80  are pivotally secured to the slot portion  98  of the collar member  90  by a screw  91  and nut  93 , as shown in FIG.  4 . Also, as shown in FIG. 4, a substantially cylindrical sleeve member  110  may be employed between the collar member  90  and the rib member  70  to reinforce the support provided by the strut member  80  to the rib member  70 . In one embodiment of the invention, the sleeve member  110  is made of aluminum. 
     As shown in FIGS. 1 and 2, a retaining pin  112  is attached to the main hub member  18  and can be placed within a retaining pin slot  114  in the pole  12  in order to maintain the vertical position of the main hub member  18  along the pole. The pin  112  is secured to the main hub member so as to allow the free rotation of the hub members  18 ,  30  about the pole even when the pin  112  is in place within the pin retaining slot  114 . As shown in FIGS. 1 and 2, the pin  112  is maintained around the waist portion  28  of the main hub member by a looped line  116  which allows the main hub member to rotate without binding the line. The main hub member may also be formed of two pieces and may employ ball or roller bearings or the like to allow the two pieces to move independently of one another in a lateral direction, while still moving as a single unit up and down the pole. Such an arrangement allows the retaining pin to remain within its slot and thereby maintain the main hub member in the upper, frame extended, position while allowing the umbrella canopy frame assembly to be freely rotated about the pole axis. 
     In operation, any desired number and size of rib and strut members may be employed, depending on the particular size and shape of the umbrella canopy to be attached. Because the hub connector joints and collar members are so easily installed, many different configurations of the canopy can be achieved with little effort by either increasing or decreasing the number of hub connector joints present on the hub members. For example, as shown in FIGS. 5 through 9, four rib members  70  are employed for the square shaped canopy  122  (FIG.  5 ), eight rib members  70  are employed for the octagonal shaped canopy  124  (FIG.  6 ), three rib members  70  are employed for the triangular shaped canopy  126  (FIG.  7 ), six rib members  70  are employed for the rectangular shaped canopy  128  (FIG. 8) and five rib members  70  are employed for the semi-octagonal shaped canopy  130  (FIG.  9 ). The number of ribs to be employed determines the number of strut members, hub connector joints, and collar members to be employed. For example, with four rib members, four strut members, eight hub connector joints, and four collar members are employed. For proper operation, the hub connector joints must be secured within corresponding slots in the main and secondary hub members. Other geometrical shapes and sizes of canopies may also be employed using the frame assembly of the present invention. 
     Canopies of varying shapes and sizes are attached to the umbrella frame by unscrewing the finial or end cap  40  from the top end  14  of the pole  12  and removing the securing nut  17 . The canopy opening is placed over the threaded bolt  15  and the canopy cuffs are placed around the outer ends of the rib members. The securing nut  17  and finial  40  are then placed back onto the threaded bolt  15 . In one embodiment of the invention, the canopy members are SUNBRELLA 100% solution-dyed acrylic canopies or any other shade-like or non-shadelike material. 
     When the frame is in the retracted position, as shown in phantom in FIGS. 1 and 2, the main hub member  18  is near the bottom end  16  of the pole. As the main hub member  18  is lifted up the pole, the strut members  80  extend outwardly, thereby expanding the rib members  70  and opening the attached canopy  21 . As the strut members  80  pass the point where they extend perpendicularly from the pole member  12 , the strut members  80  lock into place against a hub stop member  120  secured to the pole, as shown in solid lines in FIGS. 1 and 2. The retaining pin member  112  is then placed within its slot  114  on the pole and the hub member  18  may then be returned downwardly to rest against the pin member  112 . In this position, as shown in the dashed lines in FIGS. I and  2 , the strut members  80  extend in a substantially perpendicular fashion from the pole member  12  to provide substantial support to the rib members  70 . 
     The hub connector joints  52  and the collar members  90  are of key importance in the structural and long term integrity of the umbrella unit. First, the upper portion  100  of the collar member walls  92  remain below the height of the rib members; thus, the collar members  90  avoid contacting the canopy during operation of the umbrella. Such contact could significantly damage the fabric of the canopy. Secondly, the collar members  90  and the hub connector joints  52  help maintain the rib and strut members in perfect alignment so that the two independent hubs act in concert throughout the continual opening and closing of the umbrella frame. The upper channel portions  96  of the collar members  90  cradle the rib members  70  and the slot portions  98  of the collar members as well as the hub connector joint apertures  60  straddle their respective ends of the rib  70  and strut  80  members and allow ease of pivotal motion. Due to the interchangeable and easily replaceable nature of the hub connector joints and collar members, a broken umbrella may be repaired quickly, easily and with minimal cost to the consumer. Different textures and colors of the hub members, the hub connector joints, and the collar members are also available. 
     The umbrella frame may be easily rotated by loosening the end cap  40  and securing nut  17  from the pole top end  14  and rotating the hub members  18 ,  30  to their desired location. The umbrella frame may also employ a double pulley system  45  as shown in FIG. 2, to allow the user to pull the pulley cord  47  to initiate the raising of the main hub member and thereby the opening of the umbrella. 
     The rigidity and density of all the components described herein can be tempered for a desired flexibility as needed. The pole, rib, and strut members may be comprised of metal, wood or fiberglass but not limited to these rigid compositions. The nature of thermoplastic construction with materials like ABS, DELRIN, POLYPROPOLYNE and other ACETALS allow for a degree of flexibility in the hubs, hub connector joints, and collar members of the umbrella frame. In heavy wind conditions the static frame work moves a few degrees in many directions and the tension of this movement is absorbed but not released. This type of stress over time degrades the structural integrity of an umbrella. Because these plastics have a degree of flexibility, the energy that normally would be absorbed by a completely static frame umbrella is distributed through all of the plastic components of the umbrella. This greatly increases the life of the static frame of an outdoor umbrella which is generally the more costly portion of an umbrella unit. 
     The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.