Umbrella without a positioning bow spring

Abstract

The present invention relates to an umbrella without a bow spring provided in a shaft of the umbrella. The improved umbrella is provided a special umbrella frame accompanying with a runner provided around the shaft. While the umbrella is opened, there will be an upward force acting on the runner for maintaining the umbrella in opened state. So it is unnecessary to provide a bow spring in the shaft and obtains utilized effect.

What is claimed is:  
     
         1 . An umbrella without a bow spring including a shaft having an upper joint, a runner provided around the shaft slidably, and frame having ribs to connect with the upper joint and the runner to become a normal foldable umbrella; the characteristic is that the frame including a first rib, a second rib, a third rib, a fourth rib, and a tail rib, wherein the said first rib having its inner end to connect with the upper joint and its outer end to connect with middle position of the second rib, the second rib having its inner end to connect with the runner and its outer end to connect with an inner position of the third rib, and a first branch rib being provided between outer position of the first rib and inner end of the third rib.