Roller assembly fitting device for use in a roller blind

A roller assembly fitting device for use in a roller having a roller assembly supported by a pair of mounting brackets and provided with a hollow roller on which a screen is wound, said device comprising a roller-end sleeve removably secured to the hollow roller, a guide sleeve coaxially mounted in said roller-end sleeve, said guide sleeve being rotatable between first and second angular positions in said roller-end sleeve, a pivot retractably mounted in said sleeves, said pivot passing through the respective bores in said roller-end and guide sleeves and having in the outer periphery thereof an annular step and axial and peripheral grooves, a coil spring interposed between said step and the bottom of said guide sleeve to bias them in opposite directions, said roller-end sleeve having an inner radial projection fitted in said axial groove for rotation with said pivot, said guide sleeve having an inner radial projection for selectively fitting engagement with said axial and peripheral grooves, whereby the radial projection of said guide sleeve locates in said axial groove to permit the retraction of the pivot when said guide sleeve is in the first angular position but enters said peripheral groove to lock the retraction of the pivot when said guide sleeve shifts to the second angular position.