Lock mechanism of large umbrella for effecting a section-less length adjustment of telescopic shank

Abstract

A lock mechanism mounted in a large umbrella includes a sliding sleeve connected to spreaders and including a lower extension and an aperture on a surface of the extension, a telescopic shank, a lock device disposed in the shank, an actuation assembly including a hollow upper enlargement with the extension received therein, a transverse opening formed on the enlargement, and a spring biased actuation member adapted to have a portion disposed in the aperture for locking the extension in a closed position of the umbrella, the actuation member including a trigger, and a spring biased rib fixing assembly disposed between the handle and the actuation assembly. Pushing the trigger will disengage the portion with the aperture to unlock the extension for opening the umbrella. Also, turning the lock device will effect a subsequent section-less length adjustment of the shank.

1 . A lock mechanism mounted in a large umbrella having a handle, a plurality of ribs, a plurality of spreaders, and a canopy, the lock mechanism comprising: 
 a sliding sleeve connected to the spreaders and including a lower extension and an aperture on a surface of the extension;    a shank assembly including a telescopic shank and a lock device disposed in the shank;    an actuation assembly including a hollow upper enlargement with the extension received therein, a transverse first opening formed on the enlargement, and a spring biased actuation member adapted to have a first predetermined portion disposed in the aperture for locking the extension in a closed position of the umbrella, and a second predetermined portion disposed externally of the enlargement; and    a spring biased rib fixing assembly disposed between the handle and the actuation assembly, the rib fixing assembly being adapted to fix tips of the ribs in the closed position of the umbrella;    whereby pushing the second predetermined portion of the actuation assembly will disengage the first predetermined portion with the aperture to unlock the extension of the sliding sleeve for sliding the sliding sleeve upward to open the umbrella, and turning the lock device of the shank assembly will effect a subsequent section-less length or section-more length adjustment of the shank.    
   
   
       2 . The lock mechanism of  claim 1 , wherein the shank comprises a fixed lower tube, a sliding upper tube adapted to partially slide into the lower tube, a coupling disposed on an upper end of the lower tube, and a lock device secured to a lower end of the upper tube.  
   
   
       3 . The lock mechanism of  claim 2 , wherein the lock device comprises a barbell member secured to the lower end of the upper tube and including an eccentric groove formed on an intermediate portion, an eccentric bar formed adjacent the groove, and a projecting stop formed on a surface of the bar; and a flexible, eccentric C-shaped fastening member fitted on the groove.  
   
   
       4 . The lock mechanism of  claim 3 , wherein the fastening member comprises an eccentric arcuate first member, an eccentric arcuate second member thinner than the first member, and a flexible portion interconnected the first and the second members, and a protuberance formed on a top of the second member.  
   
   
       5 . The lock mechanism of  claim 2 , wherein the coupling comprises a top narrow section having an inner diameter smaller than that of the lower tube for preventing the lower tube from disengaging with the upper tube.  
   
   
       6 . The lock mechanism of  claim 1 , wherein the extension comprises two opposite projecting members formed above the aperture, and wherein the enlargement further comprises two notches on its inner surface engaged with the projecting members of the extension.  
   
   
       7 . The lock mechanism of  claim 2 , wherein the coupling has an outer diameter smaller than an inner diameter of the sleeve such that the sleeve is adapted to pass through the coupling by sliding in opening or closing the umbrella.  
   
   
       8 . The lock mechanism of  claim 1 , wherein the enlargement further comprises a receptacle opposite the first opening for anchoring the actuation member, and a lower projecting portion including a plurality of flanges formed therearound; wherein the second predetermined portion of the actuation member is formed as a trigger; and wherein the actuation member further comprises a loop interconnected the first and the second predetermined portions, a cavity formed in the first predetermined portion opposite the receptacle, and a first elastic member having one end anchored in the receptacle and the other end anchored in the cavity.  
   
   
       9 . The lock mechanism of  claim 8 , wherein the rib fixing assembly comprises a cup including a bottom second opening urged against one of the flanges, and a second elastic member compressed between the cup and the handle.  
   
   
       10 . The lock mechanism of  claim 9 , wherein the tips of the ribs are adapted to dispose proximate the cup in response to closing the umbrella.