Patent ID: 6918425

Claim:
An adjustment device for a Venetian blind connected to a window sill comprising: a) a lower beam having a fixing hole located through a top and a bottom of each of two opposing ends thereof; and b) two retaining devices, each of the two retaining devices having: i) a holding sleeve having a retaining cavity, a first end of the holding sleeve being inserted into one of the two opposing ends of the lower beam; ii) a limiting spring; iii) a driven member having a first end inserted through the limiting spring, the first end of the driven member and the limiting spring being inserted into the holding sleeve; iv) a rotary member connected to a second end of the holding sleeve and having a plurality of alternating left and right blades positioned in the retaining cavity, the rotary member being rotatable in clockwise and counter clockwise directions; and v) an outer cap connected to a second end of the holding sleeve, wherein an end of each of two retaining cords of the Venetian blind is inserted through the fixing hole in the top of one of the two opposing ends of the lower beam, through the plurality of alternating left and right blades, through the fixing hole in the bottom of one of the two opposing ends of the lower beam, and connected to a bottom of the window sill, the lower beam being movable along a length of the two retaining cords and held in a predetermined position by friction forces created by the two retaining devices.