u/Thats_Life_94

[Help needed] Issue with speed of double friction wheels

Hello everyone.

I need your diagnosis trying to recreate the Kissing couple automata by Peter Markey (for a wedding gift) with two friction wheels, using 3d printed parts. When the handle is turned slowly, the friction wheels work as intended and the head turned a full 90 degree and back in a rythmic fashion.

But when the handle is turned quickly, the friction wheels sometimes don't "grip" the flat cam follower, causing the head to turn only partially (as pictured).

In your experience, what could be the cause for this? Or is this just simple physics when the shaft is turned too quickly?

I can provide a video of the mechanism in action if needed.

Thank you!

https://preview.redd.it/ofjlg69mv6ah1.png?width=2048&format=png&auto=webp&s=724ce202b891829233af989871460708d07f9c4d

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u/Thats_Life_94 — 7 days ago

▲ 15 r/MechanicalEngineering

Help with Automata Design (Single-Slider Linear Reciprocation with Rotational Lock)

Hello everyone, first time poster and a newb here, who has no background in engineering.
I’m working on a mechanical project (an automaton bank) similar to the vintage "Love Bank" toys in the vid. I need help designing the internal linkage to achieve a specific movement.

With an ordinary crank, I was able to recreate the to-and-fro sliding mechanism, but I just can't figure out how to make the moving figure (the boy in red shirt) stay perfectly facing the girl in blue throughout the entire stroke.

Do you have any suggestions? I suppose it's a children's toy so would not be complex or difficult to manufacture.

Thank you for reading.

u/Thats_Life_94 — 2 months ago