Flat umbrella improvement structure

Abstract

A flat umbrella improvement structure is comprised of a notch and a runner, both are in flat shapes. A variety of main ribs have one ends thereof symmetrically pivoted on both sides of the curved edges of the notch and have the middle portions thereof that are pivoted to the notch on the same side of the notch designed as curved surfaces and protruded in shape, in addition, a variety of stretchers that are correspondently pivoted to the main ribs have the portions thereof connecting to the runner designed as curved protruded shapes as well. As the umbrella is collapsed, the collapsed middle radial heights of the main ribs and of the stretchers are higher than the collapsed radial heights of the rest main ribs and of the corresponding stretchers. Therefore, the umbrella of the invention is able to be collapsed tightly in a flat collapsed shape with minimum umbrella size, thereby enabling said umbrella to be easily carried and stored.

1 . A flat umbrella improvement structure, comprising a notch and a runner, both are in flat shapes; wherein the notch has the arc edges on both sides thereof symmetrically pivoted a variety of main ribs with the characteristics lie in : the main ribs on the same side of the notch have the ends of the middle main ribs thereof pivoted to the notch in bending protruded shapes; in addition, the ends of the corresponding stretchers pivoted to the runner are designed in bending protruded shapes thereby the radial heights of the middle main ribs and of the middle stretchers are higher than the radial heights of the rest main ribs and of the corresponding stretchers, when the umbrella is collapsed.  
   
   
       2 . The flat umbrella improvement structure of  claim 1 , wherein the pivotal connection portions of said main ribs and said notch are able to be either U-shaped rods, round-shaped rods or solid rods.  
   
   
       3 . A flat umbrella improvement structure, comprising a notch and a runner, both are in flat shapes; wherein the notch has the arc edges on both sides thereof symmetrically pivoted a variety of main ribs with the characteristics lie in: the main ribs on the same side of the notch have the ends of the middle main ribs thereof pivoted to the notch are “7”-shape joints, in the middle of which is a bending protruded structure and the inner sides thereof have a variety of long-shaped holes set on the joints are for ties of the notch to pierce through thereof; the ends of the corresponding stretchers pivoted to the runner are designed as “7”-shaped joints, which are designed as curved protruded structures in the middle thereof and the variety of long-shaped holes on the inner sides of the joints are for ties of the runner to pierce through thereof, thereby the radial heights of the middle main ribs and of the middle stretchers are higher than the radial heights of the rest main ribs and of the corresponding stretchers, when the umbrella is collapsed.  
   
   
       4 . The flat umbrella improvement structure of  claim 3 , wherein the notch has a locking section set on a pivotal cavity thereof, and respective supporting sections are protruded on the edges of both lateral sides of the lower portion of the notch corresponding to the collapsed positions of the joints each.  
   
   
       5 . The flat umbrella improvement structure of  claim 3 , wherein the runner has a locking section set on a pivotal cavity thereof; respective supporting sections are protruded on the edges of both lateral sides of the upper portions of the runner corresponding to the collapsed places of the joints each.