摘要 |
A lift lock for a blind is disclosed to include a casing holding a guide wheel, balls respectively received in respective sliding grooves around one side of the guide wheel, a shaft inserted through the casing and coupled to a lift rod of the blind, and a spring member sleeved onto the shaft for forcing an engagement portion of the shaft into engagement with a positioning opening of the casing. When the torque inputted into the lift rod surpassed the friction resistance between the casing and the shaft, the balls force the shaft to disengage the engagement portion from the positioning opening of the casing for enabling the lift rod to be freely rotated. When the input torque of the lift rod dropped, the spring member returns the shaft into engagement with the positioning opening of the casing to stop the lift rod in position.
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