Driving rope of large-sized umbrella

Abstract

An umbrella includes a center post having an upper end to which a crown is mounted. A number of ribs are pivoted to the crown and radially extend from the crown. A runner is movably mounted to the center post. A stretcher is mounted between the runner and each rib by having ends pivoted to the runner and the rib. A canopy is attached to and supported by the ribs. An opening/closing device includes a reel rotatably mounted in to the center post and a crank arm coupled to the reel for manually rotating the reel. A length of rope has first and second sections respectively fixed to the reel and the runner whereby by rotating the reel, the rope is wound around the reel, causing the runner to move toward the crown and driving the stretchers to expand the ribs and the canopy and thus opening the umbrella. The first and second sections of the rope have first and second diameters respectively, the first diameter being greater than the second diameter. The large first diameter helps to quickly increase the outside diameter of the reel when it is wound around the reel, thereby decreasing the force required to operate the crank for winding the rope and thus opening the umbrella.

What is claimed is:  
     
         1 . An umbrella comprising: 
 a center post;    a runner movable along the center post for opening/closing a canopy; and    an opening/closing device comprising: 
 a reel rotatably mounted to the center post, and  
 a length of a rope comprised of first and second sections having first and second diameters respectively, the first diameter being greater than the second diameter, the first section being attached to the reel to be would thereon and the second section being attached to the runner whereby by winding the first section around the reel, the rope driving the runner to move along the center post.  
   
     
     
         2 . The umbrella as claimed in  claim 1 , wherein the center post comprises a tubular member through which the rope partially extends.  
     
     
         3 . The umbrella as claimed in  claim 1 , wherein the first section of the rope comprises a tubular member having an outside diameter substantially corresponding to the first diameter, the tubular member being fit over the rope to form the first section.  
     
     
         4 . The umbrella as claimed in  claim 1 , wherein the rope is comprised of coating layers, the coating layer of the first section having a thickness greater than a thickness of the coating layer of the second section.