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Anonymous
Device that first transmits force along a rope, then stops
2016-06-02 19:15:02 Post No. 1002859
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Device that first transmits force along a rope, then stops
Anonymous
2016-06-02 19:15:02
Post No. 1002859
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I have one of those undersink slide out trash bins, but you have to lift the lid yourself which is annoying.
I'd like to make some sort of rope and pulley contraption, so that when you try to slide it out, it will automatically lift the lid slightly, and then lower it back down when you slide it back in.
I thought about it and it seems like basically my problem hinges on constructing a device that has the following characteristics (refer to pic 1):
R is a weight representing the lid. Q is the device. P is the pulley that will be routed around and tied to the base of trash can.
When the rope is pulled in given direction, both Q and R will be pulled up at first (plot showing hQ and hR). It doesn't matter if R is pulled in direct proportion to Q, hence the several dashed curves, any of which would be acceptable.
After a preset threshold is met, however, Q continues going up but R remains in place.
When the rope through P is slackened back in, the events play out in reverse: First only Q is lowered without lowering R, but when threshold is reached (ie. the trash bin has almost completely slid back in) R starts lowering as well.
