Stick umbrella structure for retracting rib units in a reverse direction

Abstract

A stick umbrella structure includes a main shank, a plurality of rib units and a canopy. A fixed hub and a movable slider are mounted on opposite ends of the main shank. The movable slider is slidably provided on the main shank and positioned at two predetermined positions. The rib unit consists of a main rib and a spreader rib. One end of the main rib pivot-connects with the movable slider. One end of the spreader rib pivot-connects with the fixed hub while the other end pivot-connects with a pivot point of the main rib. A center of the canopy is fixed to the fixed hub while an outer periphery of the canopy is fixed to the main ribs. Accordingly, the rib units are capable of unfolding the canopy by spreading the main ribs and the canopy can be folded in a reverse direction by retracting the main ribs.

1 . A stick umbrella structure comprising:
 a main shank including a fixed hub, a movable slider and at least one engaging tooth, the fixed hub being mounted on a top end of the main shank, the movable slider slidably mounted on the main shank, the engaging tooth being arranged at a position proximal a top portion of the main shank; and   a plurality of rib units each of which having a main rib and a spreader rib, the main rib having a pivot point, the spreader rib having a first end pivot-connecting with the fixed hub and a second end pivot-connecting with the pivot point of the main rib;   wherein when the rib units are retracted, the main ribs are retracted in a reverse direction with respect to the top end of the main shank.   
   
   
       2 . The stick umbrella structure as defined in  claim 1 , further comprising a canopy spread on the rib units, a center of the canopy being fixed to the fixed hub while a periphery of the canopy being fixed to the main ribs. 
   
   
       3 . The stick umbrella structure as defined in  claim 2 , wherein the canopy is further fixed to the spreader ribs. 
   
   
       4 . The stick umbrella structure as defined in  claim 1 , wherein the spreader rib has a length significantly greater than a distance between a pivot point of the movable slider and the pivot point of the main rib. 
   
   
       5 . The stick umbrella structure as defined in  claim 1 , wherein the movable slider includes an engaging hole to engage with the engaging tooth of the main shank. 
   
   
       6 . The stick umbrella structure as defined in  claim 1 , wherein the main shank further includes an elastic member located on a position of the main shank proximal the fixed hub. 
   
   
       7 . The stick umbrella structure as defined in  claim 1 , wherein the main shank further includes an umbrella handle mounted on a bottom end of the main shank. 
   
   
       8 . The stick umbrella structure as defined in  claim 1 , wherein the main shank further includes an engaging tooth arranged at a position proximal a bottom portion of the main shank. 
   
   
       9 . A stick umbrella structure comprising:
 a main shank including a fixed hub and a movable slider, the fixed hub being mounted on a top end of the main shank, the movable slider slidably mounted on the main shank and provided at least one pivot point;   at least one main rib pivot-connected with the movable slider, the main rib having a pivot point; and   at least one spreader rib the spreader rib having a first end pivot-connecting with the pivot point of the fixed hub and a second end pivot-connecting with the pivot point of the main rib;   wherein when the movable slider moves upwardly, the main rib is expanded;   wherein, conversely, when the movable slider moves downwardly, the main rib is retracted in a reverse direction with respect to the top end of the main shank.   
   
   
       10 . The stick umbrella structure as defined in  claim 9 , further comprising a canopy spread on the main rib and the spreader rib, a center of the canopy being fixed to the fixed hub while a periphery of the canopy being fixed to the main rib. 
   
   
       11 . The stick umbrella structure as defined in  claim 10 , wherein the canopy is further fixed to the spreader rib. 
   
   
       12 . The stick umbrella structure as defined in  claim 9 , wherein the spreader rib has a length significantly greater than a distance between a pivot point of the movable slider and the pivot point of the main rib. 
   
   
       13 . The stick umbrella structure as defined in  claim 9 , wherein the main shank further includes an engaging tooth arranged at a position proximal a top portion of the main shank. 
   
   
       14 . The stick umbrella structure as defined in  claim 13 , wherein the movable slider includes an engaging hole to engage with the engaging tooth of the main shank. 
   
   
       15 . The stick umbrella structure as defined in  claim 9 , wherein the main shank further includes an elastic member located on a position of the main shank proximal the fixed hub. 
   
   
       16 . The stick umbrella structure as defined in  claim 9 , wherein the main shank further includes an umbrella handle mounted on a bottom end of the main shank. 
   
   
       17 . The stick umbrella structure as defined in  claim 9 , wherein the main shank further includes an engaging tooth arranged at a position proximal a bottom portion of the main shank.