Patent ID: 9574393
Date: 2017-02-21
CPC Classifications: E06B

Claim:
1. A cord-winding device for a blind assembly having no pull cord, said cord-winding device comprising: a base seat extending along a longitudinal direction and defining a slide channel that extends along the longitudinal direction, said base seat having a bottom side configured to removably mount the blind assembly thereto; an adjustment unit including a lift cord winding around said rollers and extending through said base seat, said lift cord being configured to extend through the blind assembly after extending through said base seat so as to be positioned to said base seat and the blind assembly, said lift cord being configured to support the weight of the blind assembly to thereby generate a pulling force to pull said slide seat, said slide seat in turn pulling said constant force spring so that said constant force spring generates a resilient restoring force, the resilient restoring force counteracting the pulling force of said lift cord to achieve a force-balanced state, wherein said first end of said constant force spring is formed with a noncircular lock hole, said spring unit further including a pad that has a protrusion inserted into said lock hole, and a fastener to fix said first end of said constant force spring to said base seat.