Patent ID: 8161988

Claim:
A central shaft control structure of a self-opening closing umbrella including a control assembly with a safety device mounted inside a handle of the umbrella, wherein the safety device comprises: a base is coupled to a first shaft segment and has a front side that is made hollow to which a hole formed in the first shaft segment corresponds and further comprises a control collar that has a rear side having an inside surface to which a projecting block is provided and an outside surface biased by a spring, the control collar having a front side that is set in engagement with an inside surface of a pushbutton, the lower end of the base being coupled to a coupling seat that forms a pivot bar and a receiving channel; a barrel is fixed inside a bottom portion of the first shaft segment and forms, in a surface thereof opposing the hole of the first shaft segment, an opening that has an upper end forming an inward bent stop block and is further provided with a spring plate fixed to an inside surface thereof opposite to the opening; an operation bar has an upper end fit into the barrel and a lower end to which a single-side-inclined pawl is mounted and comprises a retention plate formed at one side thereof, a spring being provided and received in the receiving channel of the coupling seat to form a biasing engagement with the retention plate; and a reversal prevention wheel forms a pivot hole that is fit over the pivot bar of the coupling seat and has a surface that faces the operation bar and forms a toothed surface forming a plurality of ratchet teeth each having a single side inclined in a direction opposite to the inclined side of the pawl and an opposite surface forming a circular recess receiving a winding spring, the winding spring having an inner end fixed to the pivot bar and an outer end fixed to a circumferential wall of the circular recess, the reversal prevention wheel comprising a safety rope wrapping therearound and having an end fixed to the reversal prevention wheel and an opposite end extending through the base to attach to a ring of a third shaft segment.