Abstract:
Plug for capping or sealing the open ends of tubular members, such as tubular support members utilized on a Bimini boat top or other boat structure. The plug has a cap from which extend upper and lower rearwardly projecting tapered planar support panels each of which includes an outwardly protruding array of ramped teeth formed integrally therewith. The height of the teeth in each array increases incrementally from a minimum height near the end of the plug remote from the cap to a maximum height adjacent to the cap. The ramping of the teeth allows for accommodational frictional engagement of the teeth with various inside dimensions of tubular support members to secure the plug tightly therewithin. A hole extends transversely through the body of the plug for receipt of a pin for pivotally securing the end of a tubular support member containing the plug to a support bracket or other members.

Description:
CROSS REFERENCES TO CO-PENDING APPLICATIONS 
     None. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a plug, and more particularly, pertains to a plug for capping or sealing an open end of a tubular member. The plug of the invention is especially useful for capping or sealing the open ends of tubular members used for supporting purposes, and has particular application in conjunction with tubular support members utilized on boats, such as in a Bimini top or other boat structure involving tubular support members having open ends requiring capping or sealing. However, the plug is useful with tubular support members found in any other environment, or with tubular members in general. 
     2. Description of the Prior Art 
     Prior art sealing plugs for closing the open ends of tubular support members have required a number of time-consuming installation steps, such as drilling of body holes in the sides of a tubular support member for subsequent insertion of screw, bolt or pin members through the body holes into the plug to retain the plug in the open end of the tubular support member. Other plugs have been secured into the open end of a tubular support member with adhesive, only to have the adhesive deteriorate with the passage of time and with thermal changes, thereby causing the plug to disengage itself from or become loose in the tubular support member. Some plugs have formed a close tolerance fit with the interior of a tubular support member, but with age or heating and cooling have shrunk and become loose in or disengaged themselves from the tubular support member. Clearly what is needed is a plug which can be installed in the open end of a tubular support member with a minimum of tools, or even with no tools, which does not require excessive installation labor, and which is not affected by heat, cold or adhesive or material deterioration. The present invention provides such a plug. 
     SUMMARY OF THE INVENTION 
     The general purpose of the present invention is to provide a plug to be used to cap or seal the open end of a tubular member such as a tubular support member used in a boat top structure or other boat structure. Sealing of the open ends of tubular support members is accomplished for a variety of reasons. Sealing of a tubular support member on a boat prevents one from inserting a finger into the open end of the tubular support member where injury could occur during boating activities. Exposed uncapped tubular support members present sharp edges or corners which could cause bodily harm if mistakenly contacted. Sealing also prevents insects from entering or building nests in the tubular support member. The plug also aids in the connection of the tubular support member to a rail of a pleasure craft. In the plug of the invention, a series of opposing arrays of ramped teeth are included on opposing sides of the plug for the purpose of frictional engagement with the interior of a tubular support member. The teeth are ramped or sloped to provide increasing frictional contact with various wall thickness tubular support members. As the plug is inserted further into the tubular support member, the teeth are brought into increasing flex contact with the inner surfaces of the tubular support member. 
     According to one embodiment of the present invention, there is provided a plug having a plurality of connected planar members extending perpendicularly from a planar surface of a cap member. These connected planar members include horizontally oriented upper and lower tapered planar support panels, vertically oriented outer support panels and a vertically oriented center support panel extending between the horizontally oriented upper and lower tapered planar support panels, opposing arrays of ramped teeth located on the upper and lower surfaces of the horizontally oriented upper and lower tapered planar support panels and formed integrally therewith, and a series of horizontally aligned holes located in the vertically oriented outer support panels and the vertically oriented center support panel for accommodation of a mounting pin. Together the horizontally oriented upper and lower tapered planar support panels, the vertically oriented outer support panels and the vertically oriented center support panel, and the opposing integrally formed arrays of ramped teeth are inserted into the interior of a tubular support member and held therein by frictional engagement to fill and plug off the open end of the tubular support member. 
     One significant aspect and feature of the present invention is a one-piece plug which frictionally engages the open end of a tubular support member such as used in marine canopy support equipment. 
     Another significant aspect and feature of the present invention is the provision of opposing arrays of ramped teeth on the plug which increasingly engage the interior of a tubular support member in frictional engagement. 
     Another significant aspect and feature of the present invention is a plug which remains in place even with temperature excursions. 
     Another significant aspect and feature of the present invention is a plug which can be installed with a minimum of tools, or preferably with no tools. 
     Another significant aspect and feature of the present invention is a plug whose installation is not hampered by the need for drilling of holes or installation of holding pins or screws. 
     Another significant aspect and feature of the present invention is a plug including holes for accommodation of a pin used for mounting of canopy support structure. 
     Another significant aspect and feature of the present invention is a plug which is self-locating and self-aligning. 
     Another significant aspect and feature of the present invention is a plug which seals the open end of a tubular support member for prevention of bodily injury. 
     Another significant aspect and feature of the present invention is a plug which seals the open end of a tubular support member to prevent the entry of insects, debris, water and the like. 
     Having thus described significant aspects and features of an embodiment of the present invention, it is the principal object of the present invention to provide a plug for capping or sealing the open end of a tubular support member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein: 
     FIG. 1 illustrates an isometric view of a plug; 
     FIG. 2 illustrates a side view of the plug; 
     FIG. 3 illustrates a top view of the plug; 
     FIG. 4 illustrates an end view of the plug; 
     FIG. 5 illustrates a side view of the plug in frictional engagement with a tubular support member which is shown partially and in cross section; and, 
     FIG. 6 illustrates the use of the plug connecting a tubular support member to a rail. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 illustrates an isometric view of a one-piece plug 10 such as is used to seal off or close the open ends of tubular support members, such as, but not limited to, square or other rectangular tubular support members on a Bimini boat top or other boat structure having a tubular support member requiring plugging or capping. The one-piece plug 10, fashioned of plastic, rubber or other such suitable material, includes a cap 12 from which a plurality of rearwardly projecting and connected planar support panels extend. An upper tapered planar support panel 14 extends horizontally and rearwardly from the cap 12 and includes opposing tapered edges 14a and 14b, the tapers of which are widest near the junction of the cap 12 and the tapered edges 14a and 14b and narrowest near tapered locator or guide edges 14c and 14d, respectively, which are located at the inboard end of the plug 10. With respect to the centerline of the plug 10, the taper of tapered edges 14c and 14d exceeds that of the tapered edges 14a and 14b so that tapered edges 14c and 14d serve as alignment enhancing surfaces for facilitating insertion of the plug 10 into open tubular support member ends, while the tapered edges 14a and 14b serve as alignment surfaces for deeper tubular support member penetration. With reference to FIGS. 1 and 2, an outwardly protruding array of ramped teeth 16a-16n is located on the upper or top surface 14e of the upper planar support panel 14. The angle or pitch of tooth 16a is shallower than that of teeth 16b-16n to generally replicate the same angle as presented by the tapered edges 14c and 14d to aid in initial location and insertion of the plug 10 into an open tubular support member end. The angle or pitch of teeth 16b-16n with respect to the top surface 14e is greater than that angle or pitch between the top surface 14e and the angle presented by tooth 16a. As illustrated in FIGS. 2, 3 and 4, a similarly fashioned lower tapered planar support panel 18 extends horizontally and rearwardly from the cap 12 and includes opposing tapered edges 18a and 18b, the tapers of which are widest near the junction of the cap 12 and the tapered edges 18a and 18b and narrowest near tapered locator or guide edges 18c and 18d, respectively, which are located at the inboard end of the plug 10. With respect to the centerline of the plug 10, the taper of tapered edges 18c and 18d exceeds that of the tapered edges 18a and 18b so that tapered edges 18c and 18d serve as alignment enhancing surfaces for facilitating insertion of the plug 10 into open tubular support member ends, while the tapered edges 18a and 18b serve as alignment surfaces for deeper tubular support member penetration. An outwardly protruding array of ramped teeth 20a-20n is located on the lower or bottom surface 18e of the lower planar support panel 18. The angle or pitch of tooth 20a is shallower than that of teeth 20b-20n to generally replicate the same angle as presented by the tapered edges 18c and 18d, as well as tapered edges 14c and 14d, to aid in initial location and insertion into an open tubular support member end. The angle or pitch of teeth 20b-20n with respect to the bottom surface 18e is greater than that angle or pitch between the bottom surface 18e and the angle presented by tooth 18a. Outer vertically oriented support panels 22, 24 and a center vertically oriented support panel 26 align supportively between the upper tapered planar support panel 14 and the lower tapered planar support panel 18, and also intersect the cap 12 to lend rigidity between the upper and lower tapered planar support panels 14 and 18 and to the overall structure of the plug 10. Weight reducing voids 28 and 30 are formed between the outer vertically oriented support panels 22, 24, the center vertically oriented support panel 26, the upper and lower tapered planar support panels 14 and 18, and the cap 12. Horizontally aligned holes 32a, 32b and 32c mutually align in vertical support panels 22, 26 and 24, respectively, as illustrated in FIG. 4, to accommodate a connection pin, shown later in detail. 
     FIG. 2 illustrates a side view of the plug 10, where all numerals correspond to those elements previously described. Illustrated in particular is the arrangement of the ramped teeth 16a-16n and 20a-20n which engage the interior of a tubular support member as shown in FIG. 5. With respect to the horizontally aligned upper tapered planar support panel 14 and the centerline of the plug 10, it can be seen that, starting from the right side of the plug 10, the height of the teeth 16a-16n increases incrementally in a ramped fashion from right to left having a maximum tooth height nearest the cap 12. The ramping of the teeth 16a-16n allows for accommodational frictional engagement with various inside dimensions of tubular support members. The teeth 16a-16n, being narrower at the outer teeth tip areas, flex during frictional engagement and flex in increasing degrees along the plurality of teeth 16a-16n, to firmly engage the interior of a tubular support member. A number of adjacent teeth in the plurality of teeth 16a-16n progressively and in unison with opposing like teeth 20a-20n, grip the interior of the tubular support member in wedge-like fashion. 
     FIG. 3 illustrates a top view of the plug 10, where all numerals correspond to those elements previously described. Illustrated in particular are the tapered edges 14a, 14c, 14b and 14d of the upper planar support panel 14 which have corresponding tapered edges 18a, 18c, 18b and 18d located on the lower planar support panel 18, as illustrated in FIG. 4. The taper of tapered edges 14c and 14d exceeds that of the tapered edges 14a and 14b so that tapered edges 14c and 14d serve as alignment enhancing surfaces for facilitating location and insertion of the plug 10 into the open tubular support member end, while the tapered edges 14a and 14b serve as alignment surfaces for deeper tubular support member penetration. Tapered edges 18a, 18c, 18b and 18d are incorporated and function in a similar fashion. 
     FIG. 4 illustrates an end view of the plug 10, where all numerals correspond to those elements previously described. Illustrated in particular is the alignment of the holes 32a, 32b and 32c in the outer support panel 22, the center support panel 26, and the outer support panel 24, respectively. 
     FIG. 5 illustrates a side view of plug 10 in frictional engagement with a tubular support member 34 which is shown partially and in cross section, where all numerals mentioned before correspond to those elements previously described. The tubular support member 34, being of nominal wall thickness, is shown in frictional engagement with teeth 16n and 16e on the upper region of the plug 10 and in frictional engagement with teeth 20n and 20e on the lower region of the plug 10. Teeth 16n and 20n, having the greatest offset from the centerline of the plug, are in flexed impingement with the interior surfaces of the walls 34a and 34b, respectively, of the tubular support member 34. Teeth 16e and 20e tangentially impinge the interior surfaces of the walls 34a and 34b, respectively, of the tubular support member 34 in concert with teeth 16n and 20n and in combination to frictionally engage and secure the plug 10 to the interior of the tubular support member 34. It can be seen that a tubular support member having a thicker wall thickness would additionally engage an increased number of teeth, such as teeth 16d and 16c and teeth 20d and 20c, for purposes of illustration, whereby engagement and flexing of an increased number of teeth would occur and increase the holding power via increased frictional engagement. The plug 10 is inserted into the end of the tubular support member 34 until the cap 12 comes in contact with the end of the tubular support member 34. Thus, the plug 10 is incorporated into the end of a tubular support member 34 to seal the end to prevent entry of fingers as well as other objects such as dirt, insects, moisture and the like. In addition, a pin is usually inserted through holes 32a, 32b and 32c and corresponding holes in the tubular support member 34 to anchor the tubular support member 34 to a mounting structure such as, but not restricted to, nautical support rails and other supports. The pin 46, illustrated in FIG. 6, also serves as an additional means of securement of the plug 10 in the end of the tubular support member 34. 
     FIG. 6 illustrates the use of the plug 10, the present invention, where all numerals mentioned before correspond to those elements previously described. The plug 10, shown in simplified form, frictionally engages the end of tubular support member 34, and the end of the tubular support member 34 containing the plug 10 is aligned between opposing sides 38 and 40 of a mounting bracket 42 which is mounted on support structure such as a boat rail 44. The sides 38 and 40 of the mounting bracket 42 include opposing holes 38a and 40a, respectively, which align with plug 10 holes 32a, 32b and 32c previously described. A pin 46, having a tapered end 48, a ring 50, and one or more spring loaded ball latches 52, is inserted through hole 40a in the mounting bracket side 40, through the holes 32a, 32b and 32c in the plug 10, and then through hole 38a in the mounting bracket side 38 to pivotally secure the end of the tubular support member 34 to the mounting bracket 42 and thus to the boat rail 44. One or more ball latches 52 pass through the hole 38a in the mounting bracket 42 to retain the pin 46. 
     Although the plug 10 is illustrated and described as being generally square in shape, the plug 10 could take on rectangular shapes other than square, could be of other polygonal shapes, or could even have a geometrical shape other than polygonal for use with tubular members having correspondingly shaped interiors. Also, the weight reducing voids 28 and 30 could be eliminated, thus giving the plug 10 a generally solid form. Still further, the end of the cap can be substantially flat, as illustrated, or can have a rounded form. Hence, neither the precise shape nor the exact form of the plug as illustrated in the drawings shall be deemed to be limiting to the scope of the invention. 
     Various modifications can be made to the present invention without departing from the apparent scope hereof.