Umbrella with two-piece, pivotable ribs to prevent wind damage

Abstract

An umbrella includes a mast, a hub supported by the mast, a plurality of ribs extending radially outward from the hub, and a canopy supported by the ribs. Each of the ribs comprises an inner rib section having an inner end mounted to the hub. An outer rib section is pivotably mounted to the outer end of the inner rib section. A stop means engageable by one of the inner and outer rib sections limits pivotable movement of the outer rib section with respect to the inner rib section such that when the stop means is engaged, the inner rib section and the outer rib section are substantially longitudinally aligned. When wind pressure underneath the umbrella reaches a predetermined level, the outer rib sections are pivoted upward, thereby relieving the wind pressure underneath the canopy rather than

What is claimed is:  
     
         1 . An umbrella, comprising: 
 a mast;    a hub supported by said mast;    a plurality of ribs extending radially outward from said hub; and    a canopy supported by said ribs,    wherein each of said ribs comprises 
 an inner rib section having an inner end mounted to said hub and an outer end;  
 an outer rib section having an inner end pivotably mounted to said outer end of said inner rib section; and  
 stop means engageable by one of said inner and outer rib sections for limiting pivotable movement of said outer rib section with respect to said inner rib section such that when said stop means is engaged, said inner rib section and said outer rib section are in predetermined alignment;  
   whereby when wind pressure underneath said canopy reaches a predetermined level, said outer rib sections are pivoted upward with respect to said inner rib sections, thereby relieving said wind pressure underneath said canopy.    
     
     
         2 . The umbrella of  claim 1 , further comprising a housing fixedly mounted to said outer end of said inner rib section, and 
 wherein said inner end of said outer rib section being pivotably mounted to said outer end of said inner rib section comprises said inner end of said outer rib section being pivotably mounted to said housing; and    wherein said stop means engageable by one of said inner and outer rib sections for limiting pivotable movement of said outer rib section with respect to said inner rib section comprises a wall of said housing extending beyond and parallel to a bottom wall of said inner rib section and being disposed to be engaged by a bottom wall of said outer rib section when said outer rib section pivots into a position that is in predetermined alignment with said inner rib section.    
     
     
         3 . The umbrella of  claim 3 , wherein said position in which said outer rib section is in predetermined alignment with said inner rib section is a position in which said outer rib section is substantially longitudinally aligned with said inner rib section.  
     
     
         4 . The umbrella of  claim 1 , further comprising a housing fixedly mounted to said inner end of said outer rib section, and 
 wherein said inner end of said outer rib section being pivotably mounted to said outer end of said inner rib section comprises said housing being pivotably mounted to said outer end of said inner rib section; and    wherein said stop means engageable by one of said inner and outer rib sections for limiting pivotable movement of said outer rib section with respect to said inner rib section comprises a wall of said housing extending beyond and parallel to a bottom wall of said outer rib section and being disposed to be engaged by a bottom wall of said inner rib section when said outer rib section pivots into a position that is in predetermined alignment with said inner rib section.    
     
     
         5 . The umbrella of  claim 3 , wherein said position in which said outer rib section is in predetermined alignment with said inner rib section is a position in which said outer rib section is substantially longitudinally aligned with said inner rib section.