Automatic offset umbrella

Abstract

An automatic umbrella having a dome, a staff and a opening and closing mechanism off center or offset from the center of the dome is described. The opening and closing mechanism includes a plurality of ribs of varying lengths, a plurality of links of varying lengths and a plurality of braces of varying lengths. The combination of ribs, links and braces enable easy and automatic opening of the umbrella.

1 . An automatic umbrella comprising: 
 a dome;    a carrying staff;    an opening and closing frame including a plurality of ribs of varying lengths, a plurality of links of varying lengths, and a plurality of braces of varying lengths;    wherein said plurality of ribs-are pivotally connected adjacent a top of said carrying staff substantially offset from a center of said dome and adapted to extend radially therefrom when said umbrella is in an open position, wherein said frame has a longitudinal axis of symmetry in which each rib present on a common side of said axis has a different length from each other; wherein said plurality of links are pivotally connected to said plurality of ribs;    and wherein said plurality of braces are pivotally connected at a first end to said plurality of links and at a second end in a movable relation to said carrying staff.    
   
   
       2 . The automatic umbrella of  claim 1 , wherein said plurality of links are in equal number to said plurality of ribs, wherein a first end of each of said plurality of links is connected by means of a first pivot connection to a first ring member movably mounted on said carrying staff and a second end of each of said plurality of links is connected to one of said plurality of ribs by means of a first pivot point; and wherein said plurality of braces are in equal number to said plurality of links, wherein said first end of each of said plurality of braces is connected to a corresponding link of said plurality of links by means of a second pivot point and said second end of each of said plurality of braces is connected by means of a second pivot connection to a second ring member movably mounted on said carrying staff, wherein each of said plurality of links between said second pivot point that connects each of said plurality of links to a corresponding brace of said plurality of braces and said first pivot connection that connects each of said plurality of links to said first ring member is a link portion and each said link portion on said common side of said axis of symmetry is of a different length from each other.  
   
   
       3 . The automatic umbrella of  claim 2 , wherein a difference between a length of a first brace of said plurality of braces and a length of a corresponding link portion is equal to a difference between a length of any brace of said plurality of braces and a corresponding link portion thereof.  
   
   
       4 . The automatic umbrella of  claim 3 , wherein said difference between said length of each brace of said plurality of braces and said length of said corresponding link portion is equal to a distance between said first pivot connection on said first ring member and said second pivot connection on said second ring member when said first ring member and said second ring member are in a closed umbrella position.  
   
   
       5 . The automatic umbrella of  claim 4 , further comprising a propulsive spring between said first ring member and said second ring member which adjusts between a compressed position when said umbrella is in a closed position and a stretched position when said umbrella is in said open position.  
   
   
       6 . The automatic umbrella of  claim 5 , wherein said carrying staff has a button which releases said propulsive spring from said compressed position to said stretched position thereby opening said automatic umbrella.