Rib assembly having function of closing spring for helping closing of multiple-fold umbrella

Abstract

A rib assembly for multiple-fold umbrella includes: a top rib pivotally secured to an upper notch on a top of a central shaft, a stretcher rib pivotally secured between the top rib and a lower runner slidably held on the central shaft, an intermediate rib pivotally securable to the top rib or the stretcher rib, and a tail (or outer) rib pivotally connected to the intermediate rib; wherein either the top rib or the stretcher rib is formed as a lotus-shape rib when opening the umbrella; and upon opening of the umbrella, the lotus-shape ribs will be arcuately bent to store their resilience; and upon closing of the umbrella, the lotus-shape ribs will restore to release their resilience energy to automatically close the rib assembly. The rib assembly plays double duties both for supporting the umbrella cloth on the ribs and also for serving as “closing springs” for automatically closing the umbrella by eliminating the installation of closing springs on the rib assembly.

1 . A rib assembly for multiple-fold umbrella comprising: 
 a top rib pivotally secured to an upper notch formed on a top of a central shaft;    a stretcher rib pivotally connected between the top rib and a lower runner slidably held on said central shaft;    an intermediate rib pivotally connected to said top rib and pivotally connected to said stretcher rib through a connecting rib; and    a tail rib pivotally connected to said intermediate rib and pivotally connected to said top rib through a spring rib slidably coupled to said intermediate rib;    the improvement which comprises: 
 said rib assembly including a lotus-shape rib selected from the group consisting of said top rib and said stretcher rib, a plurality of said lotus-shape ribs disposed around said central shaft and operatively bent to form a lotus shape arrangement to store resilience as resiliently urged by a spring means in said shaft when opening the umbrella; and upon closing of the umbrella by releasing the spring means, the lotus-shape ribs will restore to release the resilience thereof to retract the rib assembly for automatically closing the umbrella.  
   
     
     
         2 . A rib assembly according to  claim 1 , wherein each said top rib includes: a pair of elastic plates bifurcated inwardly towards the central shaft from a middle portion of the top rib, having an inner end of each said elastic plate fixed in a sleeve member pivotally secured on the upper notch on the shaft and having an outer end of each said elastic plate inserted in a middle portion of the top rib; having the middle portion of the top rib pivotally connected to the stretcher rib and having an outer end portion of the top rib pivotally connected with the intermediate rib; whereby upon opening of the umbrella, the elastic plates of the top ribs will form a lotus shape arrangement by arcuately bending the elastic plates to store resilience of the elastic plates as urged by a spring means of the umbrella; and upon closing of the umbrella by releasing the tension of the spring means, the elastic plates of lotus shape will restore to flatten the plates to release the resilience to retract the rib assembly for automatically closing the umbrella.  
     
     
         3 . A rib assembly according to  claim 1 , wherein each said stretcher rib includes: a sleeve member pivotally secured to the lower runner slidably held on the central shaft; a pair of elastic plates having their inner ends fixed in the sleeve member and bifurcated outwardly from the central shaft to have two outer ends of two elastic plates to be pivotally connected with a middle portion of each said top rib, whereby upon opening of the umbrella, the elastic plates of the stretcher ribs will be arcuately bent to form a lotus shape arrangement as urged by a spring in the shaft to store elasticity of the elastic plates and upon closing of the umbrella by releasing the tension of the spring, the elastic plates of lotus shape will restore to flatten the elastic plates to release the elastic energy to retract the rib assembly for automatically closing the umbrella.  
     
     
         4 . A rib assembly according to  claim 1 , wherein each said stretcher rib is made of plastic, reinforced plastic and composite materials, and including: a solid inner end portion pivotally secured to the lower runner; a solid outer end portion pivotally connected to a middle portion of the top rib; an outer portion pivotally connected to an inner end portion of the connecting rib; a longitudinal groove longitudinally recessed in the stretcher rib for receiving the connecting rib into the groove when closing the umbrella and folding the rib assembly; and a pair of reinforcing extensions longitudinally formed on opposite side portions of the stretcher rib for reinforcing the mechanical strength of the rib.  
     
     
         5 . A rib assembly for multiple-fold umbrella comprising: 
 a top rib pivotally secured to an upper notch formed on a top of a central shaft;    a stretcher rib pivotally connected between the top rib and a lower runner slidably held on said central shaft;    an intermediate rib pivotally connected to said stretcher rib and pivotally connected to said top rib through a connecting rib; and    a tail rib pivotally connected to said intermediate rib;    the improvement which comprises: 
 said rib assembly including a lotus-shape rib selected from the group consisting of said top rib and said stretcher rib, a plurality of said lotus-shape ribs disposed around said central shaft and operatively bent to form a lotus shape arrangement to store resilience as resiliently tensioned by an umbrella cloth secured on said rib assembly and locked by a catch resiliently held on said central shaft; and upon depression of said catch for unlocking the rib assembly when closing the umbrella, the lotus-shape ribs will restore to release the resilience thereof to retract the rib assembly for automatically closing the umbrella.  
   
     
     
         6 . A rib assembly according to  claim 5 , wherein each said top rib includes: a pair of elastic plates bifurcated inwardly towards the central shaft from a middle portion of the stretcher rib, having an inner end of each said elastic plate fixed in a sleeve member pivotally secured on the upper notch on the shaft and having an outer end of each said elastic plate received in a middle portion of the stretcher rib; having the middle portion of the stretcher rib pivotally connected with the outer ends of the elastic plates of the top rib; whereby upon opening of the umbrella, the elastic plates of the top ribs will form a lotus shape arrangement by arcuately bending the elastic plates to store resilience of the elastic plates as tensioned by the umbrella cloth and the rib assembly of the umbrella as locked by the catch on the shaft; and upon closing of the umbrella by depressing the catch to unlock the rib assembly, the elastic plates of lotus shape will restore to flatten the plates to release the resilience to retract the rib assembly for automatically closing the umbrella.  
     
     
         7 . A rib assembly according to  claim 5 , wherein each said stretcher rib includes: a sleeve member pivotally secured to the lower runner slidably held on the central shaft; a pair of elastic plates having their inner ends fixed in the sleeve member and bifurcated outwardly from the central shaft to have two outer ends of two said elastic plates fixed in a middle portion of each said stretcher rib, whereby upon opening of the umbrella, the elastic plates of the stretcher ribs will be arcuately bent to form a lotus shape arrangement as tensioned by the umbrella cloth and the rib assembly to store elasticity of the elastic plates as locked by said catch on said shaft; and upon closing of the umbrella by depressing the catch on the shaft, the elastic plates of lotus shape will restore to flatten the elastic plates to release the elastic energy to retract the rib assembly for automatically closing the umbrella.