Patent ID: 6973952
Filing Date: 2005-12-13
Classification: E06B

Abstract:
1. An anti-reverse transmission apparatus for use in a window blind having a headrail, a blind body suspended from said headrail, and a linking rod fastened rotatably inside said headrail for lifting or lowering said blind body when said linking rod is actuated to rotate, the anti-reverse transmission apparatus comprising: a base frame having a fixed axle; an input shaft rotatably mounted to said base frame and rotatable by an external force; an output shaft having a tubular shaft body rotatably sleeved onto said fixed axle of said base frame and coupled to said input shaft for rotation by said input shaft, the tubular shaft body of said output shaft having an opening in a periphery thereof; a transmission shaft adapted to be axially coupled to said linking rod of the window blind for synchronous rotation, said transmission shaft having a tubular body sleeved onto the tubular shaft body of said output shaft, the tubular body of said transmission shaft having a protrusion projecting from an inside wall thereof and suspended in the opening of the tubular shaft body of said output shaft; and a spiral spring having a spiral spring body, a first end tip extended from a first end of said spiral body, and a second end tip extended from a second end of said spiral spring body, the spiral spring body of said spiral spring being fitted onto said fixed axle of said base frame within the tubular shaft body of said output shaft, the first and second end tips of said spiral spring being suspended in the opening of the tubular shaft body of said output shaft at two sides of the protrusion of said transmission shaft and respectively stopped at two opposite side edges of the opening of the tubular shaft body of said output shaft such that said output shaft pushes one end tip of said spiral spring to further radially expand said spiral spring body of said spiral spring when said output shaft is actuated by said input shaft to rotate; when said output shaft is immovable, rotating said transmission shaft causes said protrusion of said transmission shaft to push one end tip of said spiral spring and to further radially compress said spiral spring body of said spiral spring; wherein said transmission shaft comprises a shaft member having said tubular body and a plurality of spaced hooks axially and eguiangularly extended from the periphery of the tubular body, and a coupling member being a circular box having an axially extended center through hole adapted to be coupled to said linking rod and a plurality of retaining notches respectively fastened to said hooks of said shaft member.