by ClaireTurner »
Thu Jun 04, 2015 12:04 pm
The string (part 3) is the devil. Without it the blind won't behave - it keeps descending after I stop pulling the chain. It is attached to part 4 and the wheel housing bit of part 5 - it turns with the wheel. It winds round the big capstan of part 5 and one of either 1 or 2. So it winds and unwinds when I pull the chain and the blind goes up or down.
Part 1 goes on part 5, teeth out, and meshes with 2, which goes into 4. 2's 'wings' push against the conical inside of 4 and press the teeth together. So complicated.
When the blind goes up the teeth lock, when it goes down the teeth can unmesh, depending on the pressure from 2, because of its wings.